chore(deps): update cgrindel/gha_join_jobs digest to 8a9736c (#21)

This PR contains the following updates:

| Package | Type | Update | Change |
|---|---|---|---|
|
[cgrindel/gha_join_jobs](https://redirect.github.com/cgrindel/gha_join_jobs)
| action | digest | `794a2d1` -> `8a9736c` |

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.github/workflows/ci.yaml

@@ -142,6 +142,6 @@ jobs:
       - integration_tests
     if: ${{ always() }}
     steps:
-      - uses: cgrindel/gha_join_jobs@794a2d117251f22607f1aab937d3fd3eaaf9a2f5 # v1
+      - uses: cgrindel/gha_join_jobs@8a9736c29a7e5ebd9f3af2870f59cb6d563b6659 # v1
         with:
           github_token: ${{ secrets.GITHUB_TOKEN }}