Add release build for intel macOS

.github/workflows/main.yml

@@ -36,7 +36,12 @@ jobs:
         run: make
 
   build-macos:
-    runs-on: macos-latest
+    strategy:
+     matrix:
+       os: [macos-latest, macos-13]
+    runs-on: ${{ matrix.os }}
+    env:
+      BUILD_NAME: porymap-${{ matrix.os }}-${{ github.ref_name }}
     steps:
       # Checks-out your repository under $GITHUB_WORKSPACE, so your job can access it
       - uses: actions/checkout@v4
@@ -61,19 +66,19 @@ jobs:
       - name: Prep Release Directory
         if: startsWith(github.ref, 'refs/tags/')
         run: |
-          mkdir porymap-macOS-${{ github.ref_name }}
-          cp porymap.dmg porymap-macOS-${{ github.ref_name }}/porymap.dmg
-          cp RELEASE-README.txt porymap-macOS-${{ github.ref_name }}/README.txt
+          mkdir $BUILD_NAME
+          cp porymap.dmg $BUILD_NAME/porymap.dmg
+          cp RELEASE-README.txt $BUILD_NAME/README.txt
 
       - name: Bundle Release Directory
         if: startsWith(github.ref, 'refs/tags/')
-        run: zip -r porymap-macOS-${{ github.ref_name }}.zip porymap-macOS-${{ github.ref_name }}
+        run: zip -r $BUILD_NAME.zip $BUILD_NAME
 
       - name: Release
         uses: softprops/action-gh-release@v2
         if: startsWith(github.ref, 'refs/tags/')
         with:
-          files: porymap-macOS-${{ github.ref_name }}.zip
+          files: $BUILD_NAME.zip
         env:
             GITHUB_TOKEN: ${{ secrets.GITHUB_TOKEN }}