pgsql: Fix comments in recovery tests

Fix comments in recovery tests

Commit 4464fddf removed the large insertions but missed to remove
all the comments referring to them. Also remove a superfluous ')'
in another comment.

Author: Hayato Kuroda <kuroda.hayato@fujitsu.com>
Reviewed-by: Michael Paquier <michael@paquier.xyz>
Reviewed-by: Daniel Gustafsson <daniel@yesql.se>
Discussion: /messages/by-id/OSCPR01MB149663A99DAF2826BE691C23DF51FA@OSCPR01MB14966.jpnprd01.prod.outlook.com

Branch
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master

Details
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https://git.postgresql.org/pg/commitdiff/d8f07dbb81a169ff8d54c6684c0ca385b83de757

Modified Files
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src/test/recovery/t/046_checkpoint_logical_slot.pl | 2 +-
src/test/recovery/t/047_checkpoint_physical_slot.pl | 4 +---
2 files changed, 2 insertions(+), 4 deletions(-)