Fix to run coveralls for only one of the matrix jobs

Author: datakurre

.github/workflows/build.yml

@@ -26,6 +26,7 @@ jobs:
     - run: nix profile install nixpkgs#devenv
     - run: LC_ALL=en_US.UTF-8 make devenv-test devenv-coverage devenv-docs PYTHON=${{ matrix.python }} SPHINX=${{ matrix.sphinx }}
     - uses: coverallsapp/github-action@v2
+      if: matrix.python == 'python314' && matrix.sphinx == '8.2.3'
       with:
         debug: true
         format: cobertura