Update cmake-multi-platform.yml

Author: eel76

.github/workflows/cmake-multi-platform.yml

@@ -72,3 +72,14 @@ jobs:
     - name: Test
       working-directory: ${{ steps.strings.outputs.build-output-dir }}
       run: ctest --output-on-failure --build-config ${{ matrix.build_type }}
+
+  lint:
+    runs-on: ubuntu-latest
+    
+    steps:
+    - uses: actions/checkout@v4
+    
+    - name: Check formatting
+      run: |
+        find . -name '*.cpp' -o -name '*.h' |
+        xargs clang-format -style=file -i --dry-run --Werror