Bump DeterminateSystems/flakehub-push from 3 to 4

Bumps [DeterminateSystems/flakehub-push](https://github.com/determinatesystems/flakehub-push) from 3 to 4.
- [Release notes](https://github.com/determinatesystems/flakehub-push/releases)
- [Commits](DeterminateSystems/flakehub-push@v3...v4)

---
updated-dependencies:
- dependency-name: DeterminateSystems/flakehub-push
  dependency-type: direct:production
  update-type: version-update:semver-major
...

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

.github/workflows/publish.yml

@@ -30,7 +30,7 @@ jobs:
       - name: Install Nix
         uses: DeterminateSystems/nix-installer-action@v10
       - name: Publish flake
-        uses: DeterminateSystems/flakehub-push@v3
+        uses: DeterminateSystems/flakehub-push@v4
         with:
           tag: ${{ inputs.tag || github.ref_name }}