Bump azure/setup-helm from 3.5 to 4 (#275)

Bumps [azure/setup-helm](https://github.com/azure/setup-helm) from 3.5 to 4.
- [Release notes](https://github.com/azure/setup-helm/releases)
- [Changelog](https://github.com/Azure/setup-helm/blob/main/CHANGELOG.md)
- [Commits](Azure/setup-helm@5119fcb...b7246b1)

---
updated-dependencies:
- dependency-name: azure/setup-helm
  dependency-type: direct:production
  update-type: version-update:semver-major
...

Signed-off-by: dependabot[bot] <support@github.com>
Co-authored-by: dependabot[bot] <49699333+dependabot[bot]@users.noreply.github.com>

.github/workflows/sync-chart.yml

@@ -24,7 +24,7 @@ jobs:
           token: ${{ secrets.NGINX_PAT }}
 
       - name: Setup Helm
-        uses: azure/setup-helm@5119fcb9089d432beecbf79bb2c7915207344b78 # v3.5
+        uses: azure/setup-helm@b7246b12e77f7134dc2d460a3d5bad15bbe29390 # v4.1.0
         with:
           token: ${{ secrets.GITHUB_TOKEN }}