Bump golang from 1.21.2-alpine to 1.21.3-alpine (#216)

Bumps golang from 1.21.2-alpine to 1.21.3-alpine.

---
updated-dependencies:
- dependency-name: golang
  dependency-type: direct:production
  update-type: version-update:semver-patch
...

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Co-authored-by: dependabot[bot] <49699333+dependabot[bot]@users.noreply.github.com>

Dockerfile

@@ -12,7 +12,7 @@ RUN npm run dist
 #
 # Build backend
 #
-FROM golang:1.21.2-alpine as backend-builder
+FROM golang:1.21.3-alpine as backend-builder
 
 ARG TARGETARCH
 ARG TARGETOS