Issue title: Access API with API-KEY in case of OIDC 
 Issue body: **Is your feature request related to a problem? Please describe.**
When OIDC is enabled only the admin user/credential can use the API. In other cases it depends on the IDP or isn't possible as such.

**Describe the solution you'd like**
Harbor should extend the the "Robot Accounts" with READ/WRITE API

 Comments: 
 Comment 0: Just encoutered that problem while trying to setup replication with Harbor as Provider.
 Comment 1: We're planning to enhance the robot account in the next 2.2 version. Supporting API permission is one of the items. Please stay tuned.
 Comment 2: See also.. where i have it working with Azure AD
https://github.com/goharbor/harbor/issues/13683#issuecomment-739036574
 Comment 3: >  planning to enhance the robot account in the next 2.2 version. Supporting API permission is one of the items. Please stay tuned.

I can see the first harbor 2.2 rc has been released today. Just to clarify: Is it possible in 2.2 to assign arbitrary api permissions to a robot account or only the select 10 permissions that are shown in the GUI? (I’m interested in editing the repo description, which doesn’t work with a regular user when oidc auth is enabled).
 Comment 4: @steven-zou is this delivered in 2.2.1 already?
 Comment 5: @Morriz take a look at https://github.com/goharbor/harbor/issues/14145#issuecomment-781006533 and let us know if that did work for you

 Comment 6: got that to work! check out https://github.com/redkubes/otomi-tasks/blob/master/src/tasks/harbor/harbor.ts/
 Comment 7: This issue is being marked stale due to a period of inactivity. If this issue is still relevant, please comment or remove the stale label. Otherwise, this issue will close in 30 days.
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