Transfer ownership as administrator when repository creation is enabled

[guillep2k]

• Gitea version (or commit ref): dcb0cf7

Description

We have a setting on teams that allows members to create repositories for the organization:

The effect of this is having the user added as a collaborator with administrator permissions when the repository is created. I think we should take this setting into account when the user transfers ownership of one of their repositories into the organization. Currently the user gets a 404 error after transferring ownership because the repository doesn't belong to any of the organization teams he belongs to. I propose we add the user as a repository administrator as well in this case (only if they belong to a team with create repository permissions, of course).