[hooks/syncschema] do not crash on double removal of a constraint
Some complicated migrations may entail a double constraint removal.
It is not yet known whether this is a genuine cw bug or the result
of a complicated migration story, but we should nevertheless
not crash.
Rather, emit a CRITICAL warning and proceed.
Closes #3595309.
# -*- coding: utf-8 -*-
# copyright %(year)s %(author)s, all rights reserved.
# contact %(author-web-site)s -- mailto:%(author-email)s
#
%(long-license)s
"""%(distname)s precreate script, executed at instance creation time or when
the cube is added to an existing instance, before the schema is serialized.
This is typically to create groups referenced by the cube'schema.
"""