chore(deps): update launchdarkly/gh-actions digest to 21174f3 (#996)

This PR contains the following updates:

| Package | Type | Update | Change |
|---|---|---|---|
| launchdarkly/gh-actions | action | digest | `61ea6c6` -> `21174f3` |

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.github/workflows/shopify-oxygen.yml

@@ -32,7 +32,7 @@ jobs:
         run: yarn workspace @launchdarkly/shopify-oxygen-contract-tests build
       - name: Launch the test service in the background
         run: yarn workspace @launchdarkly/shopify-oxygen-contract-tests start &> /dev/null &
-      - uses: launchdarkly/gh-actions/actions/contract-tests@61ea6c63de800b495a2fe40c0d4e4ba2a2833ee6
+      - uses: launchdarkly/gh-actions/actions/contract-tests@21174f3a7f3aa3e3121227ec91842e8a1ebeec6e
         with:
           test_service_port: 8000
           token: ${{ secrets.GITHUB_TOKEN }}