Workaround for metadata-validation Github action's Python deps

The upstream hardware-metadata-validation action presently fails to install
Python dependencies with a permissions error for the pip cache directory. Until
it's fixed upstream, patch the action to take ownership of the directory.

.github/workflows/hardware-metadata-validation.yml

@@ -21,6 +21,8 @@ jobs:
       image: docker.io/zmkfirmware/zmk-dev-arm:3.5
     steps:
       - uses: actions/checkout@v4
+      - name: Take ownership of /github/home (temporary patch)
+        run: chown -R $(whoami) /github/home
       - name: Install dependencies
         run: pip install -r app/scripts/requirements.txt
       - name: West init