Update actions/checkout action to v4

.github/workflows/main.yml

@@ -8,7 +8,7 @@ jobs:
 
     steps:
       # Checks-out your repository under $GITHUB_WORKSPACE, so your job can access it
-      - uses: actions/checkout@v2
+      - uses: actions/checkout@v4
         with:
           # Ensures all refs and tags are fetched so "git describe --always" is working as expected
           fetch-depth: 0