Update actions/checkout digest to c2d88d3

Author: renovate[bot]

.github/workflows/label-sync.yml

@@ -9,7 +9,7 @@ jobs:
   build:
     runs-on: ubuntu-latest
     steps:
-      - uses: actions/checkout@ff7abcd0c3c05ccf6adc123a8cd1fd4fb30fb493 # pin@v2
+      - uses: actions/checkout@c2d88d3ecc89a9ef08eebf45d9637801dcee7eb5 # pin@v2
       - uses: micnncim/action-label-syncer@3abd5ab72fda571e69fffd97bd4e0033dd5f495c # pin@v1
         env:
           GITHUB_TOKEN: ${{ secrets.GITHUB_TOKEN }}