Number of required approvals MUST NOT be reset when changing assignee

Summary

The default number of required approvals is 1. A merge request set the number as 2 or more. When I assign someone, the number is reset to 1.

Steps to reproduce

1. Set the number of required approvals as 1 for a project.
2. Fork that project to your account. Actually, I'm not sure this step is important.
3. Modify something and make a merge request to the base project. At this point, set the number of required approvals as 100.
4. Change the assignee to anyone.
5. Now the number of required approvals becomes 1!

What is the current bug behavior?

The number of required approvals is reset to the default.

What is the expected correct behavior?

The number of required approvals must not be reset to the default.

Relevant logs and/or screenshots

Recorded at GitLab.com:

Output of checks

I have this problem at my GitLab EE. But I could reproduce at GitLab.com.

Results of GitLab environment info

Just GitLab.com.

Results of GitLab application Check

Just GitLab.com.

Possible fixes

Please fix it.