sagemathgh-36621: Build CI: Fix configuration of coverage upload action

    
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Fixes sagemath#36620
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URL: sagemath#36621
Reported by: Matthias Köppe
Reviewer(s): Frédéric Chapoton

.github/workflows/build.yml

@@ -193,11 +193,12 @@ jobs:
         run: |
           ./venv/bin/python3 -m coverage combine src/.coverage/
           ./venv/bin/python3 -m coverage xml
-          find . -name *coverage*
+          mkdir -p coverage-report
+          mv coverage.xml coverage-report/
         working-directory: ./worktree-image
 
       - name: Upload coverage to codecov
         if: always() && steps.build.outcome == 'success'
         uses: codecov/codecov-action@v3
         with:
-          files: ./worktree-image/coverage.xml
+          directory: ./worktree-image/coverage-report