Support ALTER DEFAULT PRIVILEGES

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Is your feature request related to a problem? Please describe.

Motivation: GRANT SELECT ON ALL TABLES IN SCHEMA public TO myuser only applies to existing tables not tables created in future.

ALTER DEFAULT PRIVILEGES can apply to future created tables. e.g.:
Grant SELECT privilege to everyone for all tables (and views) you subsequently create in schema myschema

ALTER DEFAULT PRIVILEGES IN SCHEMA myschema GRANT SELECT ON TABLES TO PUBLIC;

requested by a user.

Describe the solution you'd like

No response

Describe alternatives you've considered

No response

Additional context

https://www.postgresql.org/docs/current/sql-alterdefaultprivileges.html

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cc @yezizp2012