Add macos test

Author: Sparks29032

.github/workflows/main.yml

@@ -5,6 +5,7 @@ on:
     branches:
       - main
       - CI
+      - cookie
   pull_request:
   workflow_dispatch:
 
@@ -15,7 +16,7 @@ jobs:
     strategy:
         matrix:
             python-version: ['3.10', '3.11', '3.12']
-            os: ["ubuntu-latest", "windows-latest"]
+            os: ["macos-latest", "ubuntu-latest", "windows-latest"]
     steps:
       - name: check out diffpy.pdffit2
         uses: actions/checkout@v3