Bump sigstore/cosign-installer from 3.8.0 to 3.8.1

Bumps [sigstore/cosign-installer](https://github.com/sigstore/cosign-installer) from 3.8.0 to 3.8.1.
- [Release notes](https://github.com/sigstore/cosign-installer/releases)
- [Commits](sigstore/cosign-installer@v3.8.0...v3.8.1)

---
updated-dependencies:
- dependency-name: sigstore/cosign-installer
  dependency-type: direct:production
  update-type: version-update:semver-patch
...

Signed-off-by: dependabot[bot] <[email protected]>

.github/workflows/docker-image.yaml

@@ -33,7 +33,7 @@ jobs:
           submodules: "recursive"
 
       - name: Install cosign
-        uses: sigstore/[email protected].0
+        uses: sigstore/[email protected].1
 
       - name: Log into registry ${{ env.REGISTRY }}
         uses: docker/[email protected]