CI: Improve test matrix configuration. Add macOS, both Intel and ARM.

.github/workflows/test.yaml

@@ -12,13 +12,23 @@ concurrency:
   cancel-in-progress: true
 
 jobs:
-  build:
+  test:
-
+    name: "Python ${{ matrix.python-version }} on ${{ matrix.os }}"
-    runs-on: ubuntu-latest
+    runs-on: ${{ matrix.os }}
     strategy:
       fail-fast: false
       matrix:
-        python-version: ["3.10", "3.11", "3.12", "pypy3.10"]
+        os: [
+          "ubuntu-latest",
+          "macos-12",
+          "macos-latest",
+        ]
+        python-version: [
+          "3.10",
+          "3.11",
+          "3.12",
+          "pypy3.10",
+        ]
 
     steps:
     - uses: actions/checkout@v3