Update CI configuration to trigger on main and dev branches, and set Python version to 3.13

.github/workflows/game-ci.yml

@@ -1,10 +1,8 @@
 name: Game CI
 
 on:
-  push:
-    branches: *
   pull_request:
-    branches: [ dev ]
+    branches: [ main, dev ]
 
 jobs:
   test-game:
@@ -16,7 +14,7 @@ jobs:
     - name: Set up Python
       uses: actions/setup-python@v4
       with:
-        python-version: '3.x'
+        python-version: '3.13'
 
     - name: Install dependencies
       run: |