Move to actions/checkout@v4

.github/workflows/c-cpp.yml

@@ -70,7 +70,7 @@ jobs:
             cpp_compiler: cl
 
     steps:
-    - uses: actions/checkout@v3
+    - uses: actions/checkout@v4
 
     - name: Set reusable strings
       # Turn repeated input strings (such as the build output directory) into step outputs. These step outputs can be used throughout the workflow file.