chore(deps): update github-actions to v3

Author: renovate-bot

.github/workflows/pre-submit.units.yml

@@ -37,12 +37,12 @@ jobs:
     if: ${{ always() }}
     steps:
       - name: Checkout
-        uses: actions/checkout@7884fcad6b5d53d10323aee724dc68d8b9096a2e # tag=v2.4.2
+        uses: actions/checkout@93ea575cb5d8a053eaa0ac8fa3b40d7e05a33cc8 # tag=v3.1.0
         with:
           path: generator
 
       - name: Checkout
-        uses: actions/checkout@7884fcad6b5d53d10323aee724dc68d8b9096a2e # tag=v2.4.2
+        uses: actions/checkout@93ea575cb5d8a053eaa0ac8fa3b40d7e05a33cc8 # tag=v3.1.0
         with:
           path: verifier
           repository: slsa-framework/slsa-verifier