👷 Upgrade actions/checkout

Author: foosel

.github/workflows/custopize.yml

@@ -27,7 +27,7 @@ jobs:
     steps:
 
     - name: "⬇ Checkout"
-      uses: actions/checkout@v2
+      uses: actions/checkout@v3
 
     - name: "🔎 Determine OctoPi version"
       uses: actions/github-script@v4