replaced string `discussion` wit `thread` in comment-button template
replaced string `discussion` wit `thread` in comment-button template

stoplightio/gitlabhq,stoplightio/gitlabhq,stoplightio/gitlabhq,mmkassem/gitlabhq,mmkassem/gitlabhq,stoplightio/gitlabhq,mmkassem/gitlabhq,mmkassem/gitlabhq