Use a fixed version of checkout action with recursive

Author: aehyvari

.github/workflows/certora-prover.yml

@@ -47,10 +47,11 @@ jobs:
       - uses: step-security/harden-runner@ec9f2d5744a09debf3a187a3f4f675c53b671911
         with:
           egress-policy: audit
-      - name: Checkout repository
-        uses: actions/checkout@v4
+
+      # Checkout the repository with submodules
+      - uses: actions/checkout@11bd71901bbe5b1630ceea73d27597364c9af683
         with:
-          submodules: true
+          submodules: recursive
 
       - name: Submit verification jobs to Certora Prover
         uses: Certora/certora-run-action@v2