ci: fix checkout action submodules syntax

Author: zjp-CN

.github/workflows/test.yml

@@ -12,7 +12,8 @@ jobs:
     runs-on: ubuntu-latest
     steps:
       - uses: actions/checkout@v4
-        submodules: true
+        with:
+          submodules: 'recursive'
 
       - name: Install kani
         working-directory: kani