chore(deps): pin actions/upload-artifact action to a8a3f3a (#199)

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This PR contains the following updates:

| Package | Type | Update | Change |
|---|---|---|---|
|
[actions/upload-artifact](https://togithub.com/actions/upload-artifact)
| action | pinDigest | -> `a8a3f3a` |

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.github/workflows/ci-heavy.yml

@@ -89,7 +89,7 @@ jobs:
           INSTA_UPDATE: new
       - name: Upload snapshots of failed tests
         if: ${{ failure() && steps.run_tests.outcome == 'failure' }}
-        uses: actions/upload-artifact@v3
+        uses: actions/upload-artifact@a8a3f3ad30e3422c9c7b888a15615d19a852ae32 # v3
         with:
           name: failed-snapshots-${{ matrix.job.os }}
           path: "**/snapshots/*.snap.new"