fix(ios): ensure default icon is not flattened during maccatalyst builds to void white background (#13890)

Co-authored-by: Hans Knöchel <hansemannn@users.noreply.github.com>

Author: narbs

iphone/cli/commands/_build.js

@@ -5922,7 +5922,11 @@ iOSBuilder.prototype.createAppIconSetAndiTunesArtwork = async function createApp
 missingIcons=missingIcons.concat(awaitthis.processLaunchLogos(launchLogos,resourcesToCopy,defaultIcon,defaultIconChanged));
 
 // Do we need to flatten the default icon?
-if(missingIcons.length!==0&&defaultIcon&&defaultIconChanged&&defaultIconHasAlpha){
+letosName=this.xcodeTargetOS;
+if(this.target==='macos'||this.target==='dist-macappstore'){
+osName='maccatalyst';
+}
+if(missingIcons.length!==0&&defaultIcon&&defaultIconChanged&&defaultIconHasAlpha&&osName!=='maccatalyst'){
 this.defaultIcons=[flattenedDefaultIconDest];
 flattenIcons.push({
 name: path.basename(defaultIcon),