ci: add coverage reporting

Author: parisb

.github/workflows/pr.yaml

@@ -45,7 +45,7 @@ jobs:
     name: "Code coverage report"
     if: github.event_name == 'pull_request' # Do not run when workflow is triggered by push to main branch
     runs-on: ubuntu-latest
-    needs: unit_tests # Depends on the artifact uploaded by the "unit_tests" job
+    needs: build # Depends on the artifact uploaded by the "unit_tests" job
     permissions:
       contents: read
       actions: read # to download code coverage results from "test" job