Update mac.yml

.github/workflows/mac.yml

@@ -10,15 +10,13 @@ on:
 
 jobs:
   buildMac:
-    runs-on: macos-latest
+    runs-on: macos-12
 
     steps:
-      # Checks-out your repository under $GITHUB_WORKSPACE, so your job can access it
       - uses: actions/[email protected]
       - uses: krdlab/setup-haxe@master
         with:
           haxe-version: 4.2.5
-      # Runs a set of commands using the runners shell
       - name: Install Haxelib
         run: |
           haxelib setup ~/haxelib