client: replace the hardcoded ACCEPTED_OBJECT_TYPES by kafka introspection
Remove this global variable and check, at instanciation time, that subscribed topics exist on the kafka broker.
The semantics of the object_types
argument is thus a bit different:
if unset (None), theclient will subscribe to the whole prefix (namely it will
subscribe to "^{prefix}[.]", so any topic "under" the prefix).
Migrated from D3126 (view on Phabricator)