doc: remove "note that" from pull-requests.md

Refs: nodejs/remark-preset-lint-node#16

PR-URL: #28329
Reviewed-By: Gus Caplan <me@gus.host>
Reviewed-By: Trivikram Kamat <trivikr.dev@gmail.com>
Reviewed-By: Tobias Nießen <tniessen@tnie.de>
Reviewed-By: Ruben Bridgewater <ruben@bridgewater.de>

Author: Trott

doc/guides/contributing/pull-requests.md

@@ -134,8 +134,8 @@ $ git add my/changed/files
 $ git commit
 ```
 
-Note that multiple commits often get squashed when they are landed (see the
-notes about [commit squashing](#commit-squashing)).
+Multiple commits often get squashed when they are landed. See the
+notes about [commit squashing](#commit-squashing).
 
 #### Commit message guidelines