workflows: bump azure/setup-kubectl from 2.0 to 2.1 (#4987)

Bumps [azure/setup-kubectl](https://github.com/azure/setup-kubectl) from 2.0 to 2.1.
- [Release notes](https://github.com/azure/setup-kubectl/releases)
- [Commits](Azure/setup-kubectl@v2.0...v2.1)

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

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

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

.github/workflows/call-test-images.yaml

@@ -190,7 +190,7 @@ jobs:
           version: v3.6.3
 
       - name: Set up Kubectl
-        uses: azure/setup-kubectl@v2.0
+        uses: azure/setup-kubectl@v2.1
 
       - name: Test the HTTP server is responding
         timeout-minutes: 5