fix coveralls parallel build

Author: ntessore

.github/workflows/tests.yml

@@ -39,7 +39,7 @@ jobs:
     strategy:
       fail-fast: false
       matrix:
-        python-version: ["3.9", "3.10", "3.11", "3.12"]
+        python-version: ["3.9", "3.10", "3.11", "3.12", "3.13"]
     steps:
       - uses: actions/checkout@v4
       - uses: actions/setup-python@v5
@@ -49,8 +49,22 @@ jobs:
           cache-dependency-path: "pyproject.toml"
       - run: sudo apt-get install -y libbz2-dev # required to build fitsio
       - run: pip install -c .github/test-constraints.txt '.[test]'
-      - run: pytest --cov=heracles --cov-report=lcov
+      - run: pytest --cov=heracles --cov-report=xml
       - uses: coverallsapp/github-action@v2
+        with:
+          parallel: true
+          flag-name: run-${{ matrix.python-version }}
+
+  finish:
+    name: Finish
+    runs-on: ubuntu-latest
+    needs: test
+    if: always()
+    steps:
+      - uses: coverallsapp/github-action@v2
+        with:
+          parallel-finished: true
+          carryforward: "run-3.9,run-3.10,run-3.11,run-3.12,run-3.13"
 
   build:
     name: Build