Add filter to Doxygen

.github/workflows/build.yml

@@ -41,11 +41,13 @@ jobs:
 
     - name: Generate Doxygen documentation
       uses: mattnotmitt/doxygen-action@v1
+      if: ${{ matrix.os == 'ubuntu-20.04' && matrix.cc == 'gcc' }}
       with:
         working-directory: './build'
 
     - name: Deploy generated documentation to Github pages
       uses: peaceiris/actions-gh-pages@v3
+      if: ${{ matrix.os == 'ubuntu-20.04' && matrix.cc == 'gcc' }}
       with:
         github_token: ${{ secrets.GITHUB_TOKEN }}
         publish_dir: ./build/docs