Fail if coverage goes down (#136)

Author: ssbarnea

.github/workflows/tox.yml

@@ -106,6 +106,11 @@ jobs:
           name: logs.zip
           pattern: logs-*.zip
           delete-merged: true
+
+      - name: Check codecov.io status
+        if: github.event_name == 'pull_request'
+        uses: coactions/codecov-status@main
+
       - name: Decide whether the needed jobs succeeded or failed
         uses: re-actors/alls-green@release/v1
         with: