Fix warnings about multiple targets generating the Xcode harness
Fix warnings about multiple targets generating the Xcode harness

devoncarew/sky_engine,jamesr/flutter_engine,Hixie/sky_engine,lyceel/engine,mpcomplete/engine,abarth/sky_engine,mdakin/engine,mdakin/engine,mikejurka/engine,jason-simmons/flutter_engine,mikejurka/engine,rmacnak-google/engine,flutter/engine,jamesr/flutter_engine,afandria/sky_engine,mxia/engine,mdakin/engine,xunmengfeng/engine,tvolkert/engine,flutter/engine,flutter/engine,mxia/engine,chinmaygarde/sky_engine,mdakin/engine,jason-simmons/sky_engine,devoncarew/sky_engine,afandria/sky_engine,mikejurka/engine,abarth/sky_engine,devoncarew/sky_engine,lyceel/engine,jason-simmons/flutter_engine,flutter/engine,mxia/engine,chinmaygarde/sky_engine,devoncarew/sky_engine,jamesr/sky_engine,mxia/engine,jason-simmons/flutter_engine,krisgiesing/sky_engine,chinmaygarde/sky_engine,jason-simmons/flutter_engine,mxia/engine,lyceel/engine,qiankunshe/sky_engine,aam/engine,jamesr/sky_engine,tvolkert/engine,qiankunshe/sky_engine,qiankunshe/sky_engine,xunmengfeng/engine,jamesr/sky_engine,mpcomplete/flutter_engine,Hixie/sky_engine,krisgiesing/sky_engine,rmacnak-google/engine,mpcomplete/flutter_engine,mikejurka/engine,jason-simmons/flutter_engine,aam/engine,jason-simmons/sky_engine,jamesr/flutter_engine,devoncarew/engine,flutter/engine,jamesr/sky_engine,jamesr/flutter_engine,krisgiesing/sky_engine,jamesr/flutter_engine,aam/engine,chinmaygarde/sky_engine,jason-simmons/flutter_engine,flutter/engine,qiankunshe/sky_engine,afandria/sky_engine,mpcomplete/engine,mikejurka/engine,xunmengfeng/engine,chinmaygarde/flutter_engine,jason-simmons/flutter_engine,xunmengfeng/engine,jamesr/sky_engine,mpcomplete/engine,aam/engine,rmacnak-google/engine,afandria/sky_engine,chinmaygarde/flutter_engine,jason-simmons/flutter_engine,jamesr/flutter_engine,chinmaygarde/sky_engine,Hixie/sky_engine,rmacnak-google/engine,devoncarew/engine,mikejurka/engine,mxia/engine,krisgiesing/sky_engine,mdakin/engine,mpcomplete/flutter_engine,rmacnak-google/engine,afandria/sky_engine,afandria/sky_engine,cdotstout/sky_engine,devoncarew/engine,lyceel/engine,mdakin/engine,krisgiesing/sky_engine,abarth/sky_engine,afandria/sky_engine,qiankunshe/sky_engine,aam/engine,mxia/engine,jason-simmons/sky_engine,lyceel/engine,abarth/sky_engine,tvolkert/engine,chinmaygarde/flutter_engine,afandria/sky_engine,jason-simmons/sky_engine,jamesr/flutter_engine,mpcomplete/engine,tvolkert/engine,mpcomplete/engine,qiankunshe/sky_engine,tvolkert/engine,tvolkert/engine,abarth/sky_engine,lyceel/engine,chinmaygarde/sky_engine,devoncarew/engine,mdakin/engine,devoncarew/engine,chinmaygarde/flutter_engine,xunmengfeng/engine,abarth/sky_engine,mdakin/engine,cdotstout/sky_engine,Hixie/sky_engine,xunmengfeng/engine,qiankunshe/sky_engine,mpcomplete/flutter_engine,mxia/engine,jamesr/sky_engine,jason-simmons/sky_engine,cdotstout/sky_engine,mpcomplete/flutter_engine,jamesr/flutter_engine,Hixie/sky_engine,mikejurka/engine,abarth/sky_engine,krisgiesing/sky_engine,devoncarew/engine,rmacnak-google/engine,lyceel/engine,Hixie/sky_engine,devoncarew/sky_engine,mikejurka/engine,mpcomplete/engine,rmacnak-google/engine,krisgiesing/sky_engine,mpcomplete/engine,aam/engine,cdotstout/sky_engine,chinmaygarde/flutter_engine,jamesr/flutter_engine,jason-simmons/sky_engine,devoncarew/sky_engine,flutter/engine,mpcomplete/engine,mikejurka/engine,aam/engine,mpcomplete/flutter_engine,Hixie/sky_engine,chinmaygarde/flutter_engine,jamesr/sky_engine,jason-simmons/sky_engine,cdotstout/sky_engine,devoncarew/sky_engine,cdotstout/sky_engine,chinmaygarde/flutter_engine,devoncarew/engine,aam/engine,cdotstout/sky_engine,Hixie/sky_engine,xunmengfeng/engine,flutter/engine,qiankunshe/sky_engine,tvolkert/engine,chinmaygarde/sky_engine