Align CI with org-wide shared Python workflow template (#1006)

Add pull_request as a trigger alongside push, and enable uv's cache,
matching the pattern in meyer-lab/.github's python-uv-ruff-pytest
template. Submodule setup and coverage config are kept as-is.

Co-authored-by: Aaron Meyer <git@ameyer.me>

Author: aarmey

.github/workflows/pytest.yml

@@ -1,6 +1,8 @@
 name: Test
 
-on: [push]
+on:
+  push:
+  pull_request:
 
 jobs:
   build:
@@ -11,6 +13,8 @@ jobs:
         run: git submodule update --init --recursive
       - name: Install uv
         uses: astral-sh/setup-uv@v10.0.1
+        with:
+          enable-cache: true
       - name: Install dependencies
         run: uv sync
       - name: Lint with ruff