deps: update googleapis/java-cloud-bom digest to 47c5dbc (#2974)

[![Mend
Renovate](https://app.renovatebot.com/images/banner.svg)](https://renovatebot.com)

This PR contains the following updates:

| Package | Type | Update | Change |
|---|---|---|---|
| googleapis/java-cloud-bom | action | digest | `17cc5ec` -> `47c5dbc` |

---

> [!WARNING]
> Some dependencies could not be looked up. Check the Dependency
Dashboard for more information.

---

### Configuration

📅 **Schedule**: Branch creation - At any time (no schedule defined),
Automerge - At any time (no schedule defined).

🚦 **Automerge**: Disabled by config. Please merge this manually once you
are satisfied.

♻ **Rebasing**: Whenever PR becomes conflicted, or you tick the
rebase/retry checkbox.

🔕 **Ignore**: Close this PR and you won't be reminded about this update
again.

---

- [ ] <!-- rebase-check -->If you want to rebase/retry this PR, check
this box

---

This PR has been generated by [Mend
Renovate](https://www.mend.io/free-developer-tools/renovate/). View
repository job log
[here](https://developer.mend.io/github/googleapis/sdk-platform-java).

<!--renovate-debug:eyJjcmVhdGVkSW5WZXIiOiIzNy40MjAuMSIsInVwZGF0ZWRJblZlciI6IjM3LjQyNS4xIiwidGFyZ2V0QnJhbmNoIjoibWFpbiIsImxhYmVscyI6W119-->

Author: renovate-bot

.github/workflows/ci.yaml

@@ -327,7 +327,7 @@ jobs:
       run: |
         mvn install -B -ntp -DskipTests -Dclirr.skip -Dcheckstyle.skip
     - name: Validate gapic-generator-java-bom
-      uses: googleapis/java-cloud-bom/tests/validate-bom@17cc5ecf3730d0671f233c0879dc654337b38cba
+      uses: googleapis/java-cloud-bom/tests/validate-bom@47c5dbc0b2c9a7d120cc12eb3650db89ab5b894f
       with:
         bom-path: gapic-generator-java-bom/pom.xml