See googleapis/synthtool#2008

Author: parthea

.github/workflows/unittest.yml

@@ -30,6 +30,7 @@ jobs:
       with:
         name: coverage-artifact-${{ matrix.python }}
         path: .coverage-${{ matrix.python }}
+        include-hidden-files: true
 
   unit-prerelease:
     runs-on: ubuntu-latest