fix invalid CI skip definition

.github/workflows/tests.yml

@@ -13,7 +13,7 @@ jobs:
     continue-on-error: true
     runs-on: ubuntu-latest
     outputs:
-      should_skip: ${{ steps.skip_check.outputs.should_skip }}
+      should_skip: ${{ steps.skip_duplicate.outputs.should_skip }}
     steps:
       - id: skip_check
         uses: fkirc/skip-duplicate-actions@master
@@ -24,10 +24,7 @@ jobs:
 
   # see: https://github.com/actions/setup-python
   tests:
-    # FIXME: https://github.com/fkirc/skip-duplicate-actions/issues/90
-    #   disable for now because the tests never run... somehow similar config works in Magpie...
-    # needs: skip_duplicate
-    # if: ${{ needs.skip_duplicate.outputs.should_skip != 'true' }}
+    if: ${{ needs.skip_duplicate.outputs.should_skip != 'true' }}
     runs-on: ${{ matrix.os }}
     continue-on-error: ${{ matrix.allow-failure }}
     env: