ci: remove cache cleanup job because we are sharing cache cross branches (#5214)

.github/workflows/cache-cleanup.yml

@@ -1,36 +0,0 @@
-# https://docs.github.com/en/actions/using-workflows/caching-dependencies-to-speed-up-workflows#force-deleting-cache-entries
-name: Cleanup caches for closed branches
-
-on:
-  pull_request:
-    types:
-      - closed
-  workflow_dispatch:
-
-jobs:
-  cleanup:
-    runs-on: ubuntu-latest
-    steps:
-      - name: Check out code
-        uses: actions/checkout@v4
-
-      - name: Cleanup
-        run: |
-          gh extension install actions/gh-actions-cache
-
-          REPO=${{ github.repository }}
-          BRANCH="refs/pull/${{ github.event.pull_request.number }}/merge"
-
-          echo "Fetching list of cache key"
-          cacheKeysForPR=$(gh actions-cache list -R $REPO -B $BRANCH | cut -f 1 )
-
-          ## Setting this to not fail the workflow while deleting cache keys.
-          set +e
-          echo "Deleting caches..."
-          for cacheKey in $cacheKeysForPR
-          do
-              gh actions-cache delete $cacheKey -R $REPO -B $BRANCH --confirm
-          done
-          echo "Done"
-        env:
-          GH_TOKEN: ${{ secrets.GITHUB_TOKEN }}