fix: wrong CPU architecture while packaging macOS x64 package (#2670)

Author: love-linger

build/scripts/package.osx-app.sh

@@ -13,6 +13,13 @@ cp resources/app/App.icns SourceGit.app/Contents/Resources/App.icns
 sed "s/SOURCE_GIT_VERSION/$VERSION/g" resources/app/App.plist > SourceGit.app/Contents/Info.plist
 rm -rf SourceGit.app/Contents/MacOS/SourceGit.dsym
 rm -f SourceGit.app/Contents/MacOS/*.pdb
-clang ../tools/setsid-macos/setsid.c -o SourceGit.app/Contents/MacOS/setsid -mmacosx-version-min=13.0
+
+case "$RUNTIME" in
+  osx-arm64) arch=arm64 ;;
+  osx-x64)   arch=x86_64 ;;
+  *) echo "Unsupported RUNTIME: $RUNTIME" >&2; exit 1 ;;
+esac
+
+clang --arch "$arch" ../tools/setsid-macos/setsid.c -o SourceGit.app/Contents/MacOS/setsid -mmacosx-version-min=13.0
 
 zip "sourcegit_$VERSION.$RUNTIME.zip" -r SourceGit.app