Thanks for your feedback and advocacy on this suggestion. Bitbucket Data Center 7.13 introduces Reviewer groups that allow you to add a group of users as reviewers when creating a Pull request. Project and repository admins will be able to create and manage these groups making it easier for development teams to self-manage. You can read more details here.
Please give it a try and let us know your feedback in a comment below.
Software developer - Bitbucket Data Center
Original request description
In our workflow, any member of a team may comment on or approve most code reviews. With our previous code review systems (ReviewBoard, then gerrit) we could just add a mailing list or group to the 'Reviewer' list and this would notify all the team. However, with stash pull requests, each user needs to be added manually, which is tedious and error prone for more then a few users.