Consider propagating GRANTs for the database where Citus is installed too

With https://github.com/citusdata/citus/pull/7240, we expanded our DDL support to support propagating CREATE / DROP DATABASE commands as well as the GRANTs on those distributed databases.

However, for the database where Citus is installed, we're only propagating its owner in case of node-activation instead of sending a CREATE DATABASE command for it because it must already exist on all other nodes. Otherwise, Citus wouldn't be operational anyway.

However, we should also consider whether we need to propagate GRANTs for the database where Citus is installed, in addition to propagating its owner, in case of node activation.

See OCLASS_DATABASE in GetDependencyCreateDDLCommands().