ci: install Python test dependencies

Author: piyush-gambhir

.github/workflows/test.yml

@@ -1,8 +1,6 @@
 name: Test
 
 on:
-  push:
-    branches: [main]
   pull_request:
     branches: [main]
 
@@ -19,7 +17,7 @@ jobs:
         run: uv python install 3.12
 
       - name: Install dependencies
-        run: uv sync
+        run: uv sync --extra dev
 
       - name: Run tests
         run: uv run pytest tests/python -v