ci: store test coverage data

Author: g105b

.github/workflows/ci.yml

@@ -58,6 +58,8 @@ jobs:
           php_version: ${{ matrix.php }}
           php_extensions: xdebug
           configuration: phpunit.xml
+          coverage_text: _coverage/coverage.txt
+          coverage_clover: _coverage/clover.xml
 
       - name: Store coverage data
         uses: actions/upload-artifact@v4