Mark android_sample_catalog_generator as flaky (#14799)
Mark android_sample_catalog_generator as flaky (#14799)

https://github.com/flutter/flutter/issues/14798
cbracken/flutter,cbracken/flutter,Hixie/flutter,Hixie/flutter,flutter/flutter,tvolkert/flutter,Hixie/flutter,flutter/flutter,cbracken/flutter,cbracken/flutter,flutter/flutter,cbracken/flutter,Hixie/flutter,Hixie/flutter,tvolkert/flutter,cbracken/flutter,flutter/flutter,cbracken/flutter,cbracken/flutter,Hixie/flutter,tvolkert/flutter,tvolkert/flutter,Hixie/flutter,flutter/flutter,tvolkert/flutter,tvolkert/flutter,Hixie/flutter,tvolkert/flutter,cbracken/flutter,flutter/flutter,tvolkert/flutter,Hixie/flutter,flutter/flutter,flutter/flutter,flutter/flutter,tvolkert/flutter,cbracken/flutter,flutter/flutter,Hixie/flutter,tvolkert/flutter