LDAP override throws 404 when member has "Minimal access"

Summary

Can't "Revert to LDAP group sync settings" if member has "Minimal access"

Steps to reproduce

1. Setup LDAP in GDK
2. Create a group and setup LDAP group sync
3. Click the "Edit permissions" button next to a member
4. Change their role to "Minimal access"
5. Choose "Revert to LDAP group sync settings" in the dropdown

Example Project

What is the current bug behavior?

Reverting to group sync settings when user has "Minimal access" role causes 404

What is the expected correct behavior?

Should be able to revert to group sync settings no matter the access level the member has

Relevant logs and/or screenshots

Screen_Recording_2020-10-16_at_5.32.45_PM

Output of checks

Results of GitLab environment info

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Results of GitLab application Check

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(we will only investigate if the tests are passing)

Possible fixes