Bump golang from 475706e to 640f192

Bumps golang from `475706e` to `640f192`.

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

Signed-off-by: dependabot[bot] <support@github.com>

Dockerfile

@@ -4,7 +4,7 @@
 ## "build" stage
 ##################################################
 
-FROM --platform=${BUILDPLATFORM:-linux/amd64} docker.io/golang:1.21.0-bookworm@sha256:475706e47abe616a9d32754359d2582c26d4084dcc40de41d9f11c38b8698732 AS build
+FROM --platform=${BUILDPLATFORM:-linux/amd64} docker.io/golang:1.21.0-bookworm@sha256:640f192f24852cd875514e18a01977ae87692dca466abed7705ad3c4670b6993 AS build
 
 ARG TARGETOS
 ARG TARGETARCH