Enable macOS CI

Author: mrbbot

.github/workflows/test.yml

@@ -18,7 +18,7 @@ jobs:
 
     strategy:
       matrix:
-        os: [ubuntu-latest, windows-latest]
+        os: [ubuntu-latest, macos-latest, windows-latest]
         node: [16.13.0, latest]
         # See supported Node.js release schedule at https://nodejs.org/en/about/releases/