Fix link syntax typo
Fix link syntax typo

Fix a missing parentheses in the markdown for a link caused by the URL
containing parentheses.

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