prow-tools(deps): bump alpine in /prow/images/prow-tools (#5223)
prow-tools(deps): bump alpine in /prow/images/prow-tools (#5223)

Bumps alpine from 3.15.3 to 3.15.4.

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

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

Co-authored-by: dependabot[bot] <1c358da00a777d4e9898c1280ab801e2df165188@users.noreply.github.com>
kyma-project/test-infra,kyma-project/test-infra,kyma-project/test-infra