Enhance code coverage bot message. (#2235)

* enhance code coverage bot message. * enhance code coverage bot message. * enhance code coverage bot message. * enhance code coverage bot message. * PR feedback.

Author: codemzs

codecov.yml

@@ -11,7 +11,7 @@ coverage:
  - "build/::/"
 
 comment:
- layout: "diff,flags"
+ layout: "diff, flags, files"
 
 flags:
  production: