[test/querier] use the new connection api (part 1/3)
In devtools/repotest, we provide a simple `.qexecute` with autocommit,
and we use it (where possible) in unittest_querier.
Note that the .session object is a real session, not the magic property
found in CubicWebTC test classes.
sync_schema_props_perms(('State', 'state_of', 'Workflow'), commit=False)
sync_schema_props_perms(('State', 'name', 'String'))