cubicweb #3308564 init_repository: show error and raise if sql schema execution fails [validation pending]

As of today we swallow any error and crash a bit later because the schema is in a bad state.

prioritynormal
typebug
done in3.17.11
load0.100
load left0.000
closed by#22423634d06d [server/initrepo] show failed sql statements and abort if necessary (closes #3308564)
patch[server/initrepo] show failed sql statements and abort if necessary (closes #3308564) [applied]