chore(deps): update golang:1.21 docker digest to 81811f8 (#693)

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This PR contains the following updates:

| Package | Type | Update | Change |
|---|---|---|---|
| golang | stage | digest | `ec457a2` -> `81811f8` |

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cli/experimental/service/Dockerfile

@@ -1,4 +1,4 @@
-FROM golang:1.21@sha256:ec457a2fcd235259273428a24e09900c496d0c52207266f96a330062a01e3622 AS base
+FROM golang:1.21@sha256:81811f8a883e238666dbadee6928ae2902243a3cd3f3e860f21c102543c6b5a7 AS base
 WORKDIR /src
 ENV CGO_ENABLED=0
 COPY . ./