Lower timeout for make_membership_event
Lower timeout for make_membership_event

Calls to make_membership_event are done in response to client requests,
and so should not be retried over long timeframes.

TribeMedia/synapse,matrix-org/synapse,matrix-org/synapse,matrix-org/synapse,TribeMedia/synapse,TribeMedia/synapse,matrix-org/synapse,TribeMedia/synapse,TribeMedia/synapse,matrix-org/synapse,matrix-org/synapse