See #126412 (comment)

xcodebuild: error: Existing file at -resultBundlePath "/opt/s/w/ir/x/t/flutter_tools.LkupYt/flutter_ios_build_temp_dirlNr2gY/temporary_xcresult_bundle.xcresult"

The temp dir is generated once but we might run xcode build multiple times without delete the temp dir:
https://github.com/flutter/flutter/blob/master/packages/flutter_tools/lib/src/ios/mac.dart#LL381C30-L381C30

One fix is to clean up the xcresult bundle every time when entering this loop: https://github.com/flutter/flutter/blob/master/packages/flutter_tools/lib/src/ios/mac.dart#L517