Updated workflow to use branch code

Author: yuce

.github/workflows/tests.yaml

@@ -23,12 +23,16 @@ jobs:
 
       steps:
 
-        - name: "Checkout"
+        - name: "Checkout PR"
           uses: "actions/checkout@v4"
           if: github.event_name == 'pull_request_target'
           with:
             ref: refs/pull/${{ github.event.pull_request.number }}/merge
 
+        - name: "Checkout Branch"
+          uses: "actions/checkout@v4"
+          if: github.event_name == 'push'
+
         - name: "Set up Python ${{ matrix.python-version }}"
           uses: "actions/setup-python@v5"
           with: