[schema2sql] Avoid "parsing" SQL statements for database initialization
A big SQL string was generated, then splitted. This caused bug if some value in
the schema (eg vocabulary, default) contained the separator (';').
To properly fix this, yield each individual statement instead of generating a
string.
Closes #14050899
usr/bin/cubicweb-ctl usr/bin/
usr/lib/python2*/*-packages/cubicweb/cwctl.py
../cubicweb-ctl.bash_completion etc/bash_completion.d/cubicweb-ctl