Approve GitHub Actions for `endersonmenezes/free-disk-space@v4`

- In the file https://github.com/apache/shardingsphere/blob/master/test/native/src/test/resources/test-native/sh/free-disk-space.sh , the project currently uses a bash script—which is difficult to maintain—to free up disk space on the Ubuntu GitHub Actions runner so that Docker images can be downloaded. Approving the use of `endersonmenezes/free-disk-space@v4` (from https://github.com/endersonmenezes/free-disk-space ) would clearly simplify matters significantly.

Start with test/native/src/test/resources/test-native/sh/free-disk-space.sh and review how it frees space for Docker downloads on the Ubuntu GitHub Actions runner. Read the endersonmenezes/free-disk-space@v4 action documentation, then confirm that the requested approval can replace the current script while preserving the runner's disk-space setup.

Written by the indexing model from the issue text.