Bump docker/metadata-action from 3 to 4 (#432)

Bumps [docker/metadata-action](https://github.com/docker/metadata-action) from 3 to 4.
- [Release notes](https://github.com/docker/metadata-action/releases)
- [Upgrade guide](https://github.com/docker/metadata-action/blob/master/UPGRADE.md)
- [Commits](https://github.com/docker/metadata-action/compare/v3...v4)

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

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.github/workflows/build-latest.yaml

@@ -111,7 +111,7 @@ jobs:
           password: ${{ secrets.DOCKERHUB_PASSWORD }}
       - name: Docker meta
         id: docker_meta
-        uses: docker/metadata-action@v3
+        uses: docker/metadata-action@v4
         with:
           images: ${{ secrets.DOCKERHUB_REPO}}/postgis
           tags: |