Try and diagnose the BATS failure

.github/workflows/testing.yml

@@ -46,3 +46,19 @@ jobs:
       with:
         path: test/testdata
         only_warn: 1
+
+  diagnose_bats:
+    name: Diagnose bats
+    runs-on: ubuntu-latest
+    steps:
+      - uses: actions/checkout@v1
+      - name: Set up Python
+        uses: actions/setup-python@v2
+      - run: pip3 --quiet --quiet install git+https://github.com/codespell-project/codespell.git
+      - run: |
+          export INPUT_CHECK_FILENAMES=""
+          export INPUT_CHECK_HIDDEN=""
+          export INPUT_EXCLUDE_FILE=""
+          export INPUT_PATH="./test/testdata"
+          export INPUT_ONLY_WARN=""
+          ./entrypoint.sh