build(deps): Bump alpine in /.release in the docker group

Bumps the docker group in /.release with 1 update: alpine.


Updates `alpine` from 3.18 to 3.20

---
updated-dependencies:
- dependency-name: alpine
  dependency-type: direct:production
  update-type: version-update:semver-minor
  dependency-group: docker
...

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

.release/alpine.Dockerfile

@@ -1,4 +1,4 @@
-FROM alpine:3.18
+FROM alpine:3.20
 
 RUN apk --no-cache add \
       ca-certificates \