Update tests.yml

.github/workflows/tests.yml

@@ -1,19 +1,26 @@
 name: Unit Tests
 
+on:
+  push:
+    branches:
+      - main
 on: [push, pull_request]
+  pull_request:
+    branches:
+      - main
 
 jobs:
   build:
     runs-on: ubuntu-latest
 
     steps:
-    - name: Checkout repository
+    - name: Checkout code
       uses: actions/checkout@v4
 
     - name: Set up Python
       uses: actions/setup-python@v5
       with:
-        python-version: 3.10
+        python-version: '3.10'
 
     - name: Install dependencies
       run: |