always use bash shell

.gitea/workflows/build_pc.yml

@@ -45,6 +45,7 @@ jobs:
           key: ${{runner.os}}-cmakeChecks
       
       - name: Configure CMake
+        shell: bash
         run: |
           if [ "${{ steps.cache.outputs.cache-hit }}" != "true" ]; then
             cmake -B ${{github.workspace}}/build -DCMAKE_BUILD_TYPE=${{env.BUILD_TYPE}} -DDEPENDENCY_MIRROR_FILE="${{github.workspace}}/.gitea/workflows/DependencyMirrors.txt"