CI: Matrix on supported Python versions

Author: Epse

.github/workflows/ci.yml

@@ -10,11 +10,15 @@ on:
 jobs:
   lint:
     name: Run linting and format
+    strategy:
+      matrix:
+        # Only test a subset of python versions, to limit compute
+        python: [python3.9, python3.11, python3.13]
     runs-on: ubuntu-latest
     steps:
       - uses: actions/checkout@v4
       - uses: astral-sh/setup-uv@v6
-      - run: uv python install python3.13
+      - run: uv python install ${{ matrix.python }}
       - run: uv run ruff check src/obelisk/
       - run: uv run ruff format --check src/obelisk/
       - run: uv run mypy src/obelisk/
@@ -23,9 +27,11 @@ jobs:
     strategy:
       matrix:
         os: [ubuntu-latest, macos-latest, windows-latest]
+        # Only test a subset of python versions, to limit compute
+        python: [python3.9, python3.11, python3.13]
     runs-on: ${{ matrix.os }}
     steps:
       - uses: actions/checkout@v4
       - uses: astral-sh/setup-uv@v6
-      - run: uv python install python3.13
+      - run: uv python install ${{ matrix.python }}
       - run: uv run pytest