ci: clear out space on centos job

Clear out space on the centos job be deleteing unnecessary files.

Raised by #33293 which pointed to a solution like https://github.com/google/oss-fuzz/commit/b7f04d782277638a67bc44865de445977eed4708

Only runs when cache provider (runner) is `gha`, and on the CentOS job.

.github/workflows/ci.yml

@@ -582,6 +582,10 @@ jobs:
         with:
           cache-provider: ${{ matrix.provider || needs.runners.outputs.provider }}
 
+      - name: Clear unnecessary files
+        if: ${{ needs.runners.outputs.provider == 'gha' && true || false }} # Only needed on GHA runners
+        uses: ./.github/actions/clear-files
+
       - name: Enable bpfcc script
         if: ${{ env.CONTAINER_NAME == 'ci_native_asan' }}
         # In the image build step, no external environment variables are available,