fix: set fetch-depth to 0 in checkout step for complete history retrieval

Author: oldrev

.github/workflows/flutter-ci.yml

@@ -81,6 +81,8 @@ jobs:
     steps:
       - name: Checkout code
         uses: actions/checkout@v4
+        with:
+          fetch-depth: 0
 
       - name: Extract version & build number
         id: extract