Adding `pg_checkpoint` grant permission in `docs/advocacy_docs/supported-open-source/pgbackrest /10-non-superuser.mdx`

[CC-Hsu]

Summary

Hi, EDB team,

It would be great if this doc page Non-superuser support with pgBackRest can include pg_checkpoint predefined role for the start-fast = y setting.

Otherwise pgBackrest should wait for DB server side checkpoint_timeout triggered to start the backup process.

Best Regards.

Where would you like to see this added?

https://www.enterprisedb.com/docs/supported-open-source/pgbackrest/10-non-superuser/

Rationale

No response