Add approval rule add via LDAP list
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### Proposal
For Merge request approvals "Add approval rule". There is a box to add approvers "users or groups". We are looking to also add approved users via an LDAP list (LDAP groups cn). Similar to LDAP synchronizations "LDAP groups cn" can be used to add members, but we are looking for in "Add approval rule" for add approvers.
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