Update build.yml

.github/workflows/build.yml

@@ -8,7 +8,7 @@ jobs:
 
     strategy:
       matrix:
-        os: [macos-latest, ubuntu-latest, windows-latest]
+        os: [ubuntu-latest, macos-latest, windows-latest]
 
     steps:
     - name: Checkout repository
@@ -20,7 +20,9 @@ jobs:
         node-version: '20'
 
     - name: Install dependencies
-      run: npm ci
+      run: |
+        npm ci
+        npm i appdmg --save-optional
       working-directory: electron-3d-app
 
     - name: Package application with Electron Forge