chore(deps): update dependency webpack-cli to v4 (#310)

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This PR contains the following updates:

| Package | Change | Age | Adoption | Passing | Confidence |
|---|---|---|---|---|---|
| [webpack-cli](https://togithub.com/webpack/webpack-cli) | [`^3.3.10` -> `^4.0.0`](https://renovatebot.com/diffs/npm/webpack-cli/3.3.12/4.2.0) | [![age](https://badges.renovateapi.com/packages/npm/webpack-cli/4.2.0/age-slim)](https://docs.renovatebot.com/merge-confidence/) | [![adoption](https://badges.renovateapi.com/packages/npm/webpack-cli/4.2.0/adoption-slim)](https://docs.renovatebot.com/merge-confidence/) | [![passing](https://badges.renovateapi.com/packages/npm/webpack-cli/4.2.0/compatibility-slim/3.3.12)](https://docs.renovatebot.com/merge-confidence/) | [![confidence](https://badges.renovateapi.com/packages/npm/webpack-cli/4.2.0/confidence-slim/3.3.12)](https://docs.renovatebot.com/merge-confidence/) |

---

### Release Notes

<details>
<summary>webpack/webpack-cli</summary>

### [`v4.2.0`](https://togithub.com/webpack/webpack-cli/releases/[email protected])

[Compare Source](https://togithub.com/webpack/webpack-cli/compare/[email protected]@4.2.0)

##### Bug Fixes

-   \--config-name behaviour for functional configs ([#&#8203;2006](https://togithub.com/webpack/webpack-cli/issues/2006)) ([29ecf8d](https://togithub.com/webpack/webpack-cli/commit/29ecf8dbcd1c5c7d75fc7fb1634107697832d952))
-   assign cache value for default configs ([#&#8203;2013](https://togithub.com/webpack/webpack-cli/issues/2013)) ([d2e3c74](https://togithub.com/webpack/webpack-cli/commit/d2e3c74d32b0141c694259cf4f31e6c48b0f681d))
-   callback deprecation ([#&#8203;1977](https://togithub.com/webpack/webpack-cli/issues/1977)) ([2cb0c0e](https://togithub.com/webpack/webpack-cli/commit/2cb0c0e383670949ce31231edbfda514f47c3dfc))
-   handle core flags for webpack 4 ([#&#8203;2023](https://togithub.com/webpack/webpack-cli/issues/2023)) ([ea66a7e](https://togithub.com/webpack/webpack-cli/commit/ea66a7e3ec6eabcc439b96acb21e2a25be2e35e5))
-   help and version functionality ([#&#8203;1972](https://togithub.com/webpack/webpack-cli/issues/1972)) ([e8010b3](https://togithub.com/webpack/webpack-cli/commit/e8010b3aac695971e542ad4d3584ce534da39b8f))

##### Features

-   export utils from core for other packages ([#&#8203;2011](https://togithub.com/webpack/webpack-cli/issues/2011)) ([3004549](https://togithub.com/webpack/webpack-cli/commit/3004549c06b3fe00708d8e1eecf42419e0f72f66))
-   progress supports string argument ([#&#8203;2000](https://togithub.com/webpack/webpack-cli/issues/2000)) ([f13346e](https://togithub.com/webpack/webpack-cli/commit/f13346e6acb46e982a5d20fa1d2ae56fc52523dc))
-   suggest the closest match based on the Levenshtein distance algorithm ([#&#8203;2010](https://togithub.com/webpack/webpack-cli/issues/2010)) ([491a582](https://togithub.com/webpack/webpack-cli/commit/491a582620b64ed4acbccd04f687adc28a5e4cff))

### [`v4.1.0`](https://togithub.com/webpack/webpack-cli/releases/[email protected])

[Compare Source](https://togithub.com/webpack/webpack-cli/compare/[email protected]@4.1.0)

##### Bug Fixes

-   avoid unnecessary stringify ([#&#8203;1920](https://togithub.com/webpack/webpack-cli/issues/1920)) ([5ef1e7b](https://togithub.com/webpack/webpack-cli/commit/5ef1e7b074390406b76cb3e25dd90f045e1bd8a2))
-   colored output ([#&#8203;1944](https://togithub.com/webpack/webpack-cli/issues/1944)) ([2bbbb14](https://togithub.com/webpack/webpack-cli/commit/2bbbb14ca9a404f2205c0f5a5515e73832ee6173))
-   move init command to separate package ([#&#8203;1950](https://togithub.com/webpack/webpack-cli/issues/1950)) ([92ad475](https://togithub.com/webpack/webpack-cli/commit/92ad475d4b9606b5db7c31dd3666658301c95597))
-   output stacktrace on errors ([#&#8203;1949](https://togithub.com/webpack/webpack-cli/issues/1949)) ([9ba9d6f](https://togithub.com/webpack/webpack-cli/commit/9ba9d6f460fb25fb79d52f4360239b8c4b471451))
-   run CLI after webpack installation ([#&#8203;1951](https://togithub.com/webpack/webpack-cli/issues/1951)) ([564279e](https://togithub.com/webpack/webpack-cli/commit/564279e5b634a399647bcdb21449e5e6a7f0637e))
-   support any config name ([#&#8203;1926](https://togithub.com/webpack/webpack-cli/issues/1926)) ([6f95b26](https://togithub.com/webpack/webpack-cli/commit/6f95b267bf6a3a3e71360f4de176a4ebbec3afa1))
-   support array of functions and promises ([#&#8203;1946](https://togithub.com/webpack/webpack-cli/issues/1946)) ([2ace39b](https://togithub.com/webpack/webpack-cli/commit/2ace39b06117f558c0d8528cea9248253cbdf593))
-   watch mode and options ([#&#8203;1931](https://togithub.com/webpack/webpack-cli/issues/1931)) ([258219a](https://togithub.com/webpack/webpack-cli/commit/258219a3bb606b228636e6373a3d20413c1f660e))

##### Features

-   allow passing strings in env flag ([#&#8203;1939](https://togithub.com/webpack/webpack-cli/issues/1939)) ([cc081a2](https://togithub.com/webpack/webpack-cli/commit/cc081a256181e34137a89d2e9d37b04280b3f180))

### [`v4.0.0`](https://togithub.com/webpack/webpack-cli/blob/master/CHANGELOG.md#&#8203;400-httpsgithubcomwebpackwebpack-clicomparewebpack-cli400-rc1webpack-cli400-2020-10-10)

[Compare Source](https://togithub.com/webpack/webpack-cli/compare/[email protected])

##### Bug Fixes

-   add compilation lifecycle in watch instance ([#&#8203;1903](https://togithub.com/webpack/webpack-cli/issues/1903)) ([02b6d21](https://togithub.com/webpack/webpack-cli/commit/02b6d21eaa20166a7ed37816de716b8fc22b756a))
-   cleanup `package-utils` package ([#&#8203;1822](https://togithub.com/webpack/webpack-cli/issues/1822)) ([fd5b92b](https://togithub.com/webpack/webpack-cli/commit/fd5b92b3cd40361daec5bf4486e455a41f4c9738))
-   cli-executer supplies args further up ([#&#8203;1904](https://togithub.com/webpack/webpack-cli/issues/1904)) ([097564a](https://togithub.com/webpack/webpack-cli/commit/097564a851b36b63e0a6bf88144997ef65aa057a))
-   exit code for validation errors ([59f6303](https://togithub.com/webpack/webpack-cli/commit/59f63037fcbdbb8934b578b9adf5725bc4ae1235))
-   exit process in case of schema errors ([71e89b4](https://togithub.com/webpack/webpack-cli/commit/71e89b4092d953ea587cc4f606451ab78cbcdb93))

##### Features

-   assign config paths in build dependencies in cache config ([#&#8203;1900](https://togithub.com/webpack/webpack-cli/issues/1900)) ([7e90f11](https://togithub.com/webpack/webpack-cli/commit/7e90f110b119f36ef9def4f66cf4e17ccf1438cd))

</details>

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Author: renovate-bot

packages/google-cloud-scheduler/package.json

@@ -62,7 +62,6 @@
     "sinon": "^9.0.1",
     "ts-loader": "^8.0.0",
     "typescript": "^3.8.3",
-    "webpack-cli": "^3.3.10",
     "@microsoft/api-documenter": "^7.8.10",
     "@microsoft/api-extractor": "^7.8.10"
   }