Update checkout action version in main workflow

Author: soderlind

.github/workflows/main.yml

@@ -11,7 +11,7 @@ jobs:
     - name: Install Subversion
       run: sudo apt-get update && sudo apt-get install -y subversion
     - name: Checkout code
-      uses: actions/checkout@4
+      uses: actions/checkout@v4
     - name: WordPress Plugin Deploy
       uses: 10up/action-wordpress-plugin-deploy@stable
       env: