deps: Update actions/checkout digest to a5ac7e5 (#380)

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This PR contains the following updates:

| Package | Type | Update | Change |
|---|---|---|---|
| [actions/checkout](https://github.com/actions/checkout) | action |
digest | `b4ffde6` -> `a5ac7e5` |

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.github/workflows/labels.yaml

@@ -23,7 +23,7 @@ jobs:
   build:
     runs-on: ubuntu-latest
     steps:
-      - uses: actions/checkout@b4ffde65f46336ab88eb53be808477a3936bae11 # v4
+      - uses: actions/checkout@a5ac7e51b41094c92402da3b24376905380afc29 # v4
       - uses: micnncim/action-label-syncer@3abd5ab72fda571e69fffd97bd4e0033dd5f495c # v1
         env:
           GITHUB_TOKEN: ${{ secrets.GITHUB_TOKEN }}