Fix changing the ownership of ALL TABLES IN SCHEMA publication.

Fix changing the ownership of ALL TABLES IN SCHEMA publication.

Ensure that the new owner of ALL TABLES IN SCHEMA publication must be a
superuser. The same is already ensured during CREATE PUBLICATION.

Author: Vignesh C
Reviewed-by: Nathan Bossart, Greg Nancarrow, Michael Paquier, Haiying Tang
Discussion: https://postgr.es/m/CALDaNm0E5U-RqxFuFrkZrQeG7ae5trGa=xs=iRtPPHULtT4zOw@mail.gmail.com