[Docs] Add instructions how to remove Che user

Summary

Update: Please see https://github.com/eclipse/che/issues/17500#issuecomment-665952556

My question is: is it possible to remove an user on Che?

My motivation is: I can not start any workspace due to incorrect namespace, please see relevant info section. I tried to remove user using swagger. After removing user doesn’t exist, but after refreshing a page or at next login the system has the same user with the same ID.

Please see my short demo:

Relevant information

I faced with the problem like described here: https://github.com/eclipse/che/issues/17265#issuecomment-650947172 So:

• Che’s Keycloak shows the form with username, email, etc. when a user is trying to login into Che Dashboard the very first time
• autofill plugin sets the fields
• as result username can get incorrect value (with real names, including spaces or email for example)

Then user can not create a workspace due to not a valid namespace: The workspace would be started in a namespace/project '<incorrect value here>', which is not a valid namespace/project name.

Please see https://github.com/eclipse/che/issues/17265#issuecomment-650947172.

[ibuziuk]

@l0rd there was a request from the Toolchain team to make the Delete API call GDPR compliant and cleanup resources not only on the db level, but also on keycloak - https://github.com/eclipse/che/issues/17541 I believe we need to treat it as a high priority issue ^

[tolusha]

yes, only admin can remove user from the keycloak.