Bump docker/metadata-action from 4 to 5

Bumps [docker/metadata-action](https://github.com/docker/metadata-action) from 4 to 5.
- [Release notes](https://github.com/docker/metadata-action/releases)
- [Upgrade guide](https://github.com/docker/metadata-action/blob/master/UPGRADE.md)
- [Commits](docker/metadata-action@v4...v5)

---
updated-dependencies:
- dependency-name: docker/metadata-action
  dependency-type: direct:production
  update-type: version-update:semver-major
...

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

.github/workflows/docker.yml

@@ -25,7 +25,7 @@ jobs:
 
       - name: Set Docker metadata (Ubuntu & NVM variant)
         id: meta-ubuntu
-        uses: docker/metadata-action@v4
+        uses: docker/metadata-action@v5
         with:
           images: |
             ghcr.io/${{ github.repository }}/echidna
@@ -37,7 +37,7 @@ jobs:
 
       - name: Set Docker metadata (Distroless variant)
         id: meta-distroless
-        uses: docker/metadata-action@v4
+        uses: docker/metadata-action@v5
         if: ${{ env.WORKFLOW_BUILD_DISTROLESS == true }}
         with:
           images: ghcr.io/${{ github.repository }}/distroless