[DOC] pg_stat_replication_slots representation style inconsisitant

Hi 

When reading the manual doc, I found an inconsistent representation style for the newly added pg_stat_prefetch_recovery
viewin PG14 at [1].
 
Same problem seems to be reported by Noriyoshi Shinoda who also proposed a patch to fix the problem at[2].
I tried to fix the problem in a way different than Noriyoshi Shinoda which I think is more consistent with the existing
specificview introduction in the same page.
 
Please take the attached patch as your reference.

[1]
https://www.postgresql.org/docs/devel/monitoring-stats.html#MONITORING-PG-STAT-SUBSCRIPTION

[2]

https://www.postgresql.org/message-id/TU4PR8401MB1152945E4FD45E99C3F52B94EE4F9%40TU4PR8401MB1152.NAMPRD84.PROD.OUTLOOK.COM

Regards,
Tang