chore(deps): bump alpine from 3.21.0 to 3.21.2

Bumps alpine from 3.21.0 to 3.21.2.

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

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

Author: dependabot[bot]

Dockerfile

@@ -16,7 +16,7 @@ RUN uname -a &&\
     make build
 
 # final image
-FROM docker.io/alpine:3.21.0
+FROM docker.io/alpine:3.21.2
 
 ARG UID=10001
 ARG USER_NAME=celestia