chore(deps): update golang docker tag to v1.21 (#687)

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This PR contains the following updates:

| Package | Type | Update | Change |
|---|---|---|---|
| golang | stage | minor | `1.19` -> `1.21` |

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cli/experimental/service/Dockerfile

@@ -1,4 +1,4 @@
-FROM golang:1.19@sha256:83f9f840072d05ad4d90ce4ac7cb2427632d6b89d5ffc558f18f9577ec8188c0 AS base
+FROM golang:1.21@sha256:ec457a2fcd235259273428a24e09900c496d0c52207266f96a330062a01e3622 AS base
 WORKDIR /src
 ENV CGO_ENABLED=0
 COPY . ./