Revert "Temporarily remove workflow file"

This reverts commit abe8338.

Author: haasonsaas

.github/workflows/ci.yml

@@ -0,0 +1,21 @@
+name: ci
+
+on:
+  push:
+  pull_request:
+
+jobs:
+  test:
+    runs-on: ubuntu-latest
+    steps:
+      - uses: actions/checkout@v4
+      - uses: actions/setup-python@v5
+        with:
+          python-version: '3.11'
+      - name: Install
+        run: |
+          python -m pip install --upgrade pip
+          pip install -e .
+          pip install pytest
+      - name: Test
+        run: pytest -q