ENH: add tmate action to troubleshoot on mac (commented out for now)

It was used "actively" and worked splendid. Commenting out so
we do not end up running it regularly since it would wait us to login.

.github/workflows/base-tests.yaml

@@ -55,3 +55,8 @@ jobs:
 
       - name: Run script tests
         run: bats -t scripts/tests
+
+      # Keeping just in case to debug fails
+      #- name: Setup tmate session
+      #  if: ${{ failure() }}
+      #  uses: mxschmitt/action-tmate@v3