Add reviewers and maintainers to Danger review process

Problem to solve

We have basic Danger support added to this repo, but we don't currently have any reviewers or maintainers defined for automated reviewer suggestions.

Proposed solution

Add the following GitLab team members as reviewers/maintainers of this project. See gitlab-com/www-gitlab-com!132664 (diffs) for how the analytics stack repo was added as an example.

Reviewers	Maintainers
@ssuman3	@rob.hunt
@jiaan	@mwoolf
	@michold
	@halilcoban