[migration] don't crash when deleting a non-existing rtype When asked to delete a relation type, instead of checking if it was computed or not, just delete both the CWRType and CWComputedRType.

#! /bin/sh -e

if [ -x "/etc/init.d/cubicweb-ctl" ]; then
    invoke-rc.d cubicweb-ctl restart || true
fi
 
 
#DEBHELPER#
 
exit 0