Add coverage upload workflow

Because of credentials needed to upload to Codacy we need to add a
separate workflow which is executed in the context of the target
repository to see the credentials for uploading

.github/workflows/gcovr-ci-job.yml

@@ -115,6 +115,12 @@ jobs:
           name: "diffs-${{ inputs.container && format('docker-{0}', inputs.gcc) || format('{0}-{1}-{2}', inputs.os, inputs.gcc, inputs.python-version) }}"
           path: tests/diff.zip
 
+      - name: Upload coverage report
+        uses: actions/upload-artifact@v4
+        with:
+          name: "coverage-${{ inputs.container && format('docker-{0}', inputs.gcc) || format('{0}-{1}-{2}', inputs.os, inputs.gcc, inputs.python-version) }}"
+          path: ./coverage.xml
+
       - name: Upload coverage to Codecov
         if: ${{ (github.repository == 'gcovr/gcovr') && (env.USE_COVERAGE == 'true') }}
         uses: codecov/codecov-action@v4

.github/workflows/upload_coverage.yml

@@ -0,0 +1,22 @@
+name: Upload coverage
+
+on:
+  workflow_run:
+    workflows: ['Run GCOVR Ci']
+    types:
+      - completed
+
+jobs:
+  upload:
+    runs-on: ubuntu-22.04
+    steps:
+      - name: Download artifacts
+        uses: actions/download-artifact@v4
+        with:
+          pattern: coverage-*
+          run-id: ${{github.event.workflow_run.id }}
+
+
+      - name: List the artifacts
+        run: |
+          ls -alR .