change testoutput to GITHUB_BASE_REF

Author: knoxfighter

.github/workflows/test-workflow.yml

@@ -19,7 +19,7 @@ jobs:
  runs-on: ubuntu-latest
  steps:
  - uses: rlespinasse/github-slug-action@v3.x
- - run: echo $GITHUB_REPOSITORY_OWNER_PART
+ - run: echo $GITHUB_BASE_REF
  - name: Cancel this build
  uses: knoxfighter/cancel-action@master
  with: