cubicweb-mercurial-server #3216997 too lax permissions for hosted_by [done]

priorityimportant
typebug
done in<not specified>
load left0.000
closed by#d4a7e952e7a2 [schema] fix several permissions problems
patch[schema] fix some permissions [folded]Restrict add/delete permissions of hosted_by relation to that of Repository [applied]