I want to update commit feild description message something like "please provide here your feedback"

[Lakshman]

I want to update/customise commit field description message something like "please leave your suggestions here.." 

[Davin Studer]

You could do this with the InProduct translation for Confluence add-on. It will allow you to overrride the laguage translation resource for that section without having to get into code.

[Nic Brough -Adaptavist-]

You'll need to hack the core code of the comments system to do that. 

It is just a language thing though - the phrase is held in a file which contains wording for all languages, so if you edit the contents of that, it's only a minor change.