cubicweb-mercurial-server #3210433 move repository title constraint to sccp_base [validation pending]

the "no white space in repository.title" constraint does not belong in mercurial_server, it's only necessary in simulagora because of the MungeSourceURl hook

prioritynormal
typebug
done in0.4.0
load0.200
load left0.000
closed by#23dc357a465b [schema] Don't constrain Repository.title (closes #3210433)
patch[schema] Don't constrain Repository.title (closes #3210433) [applied]