Remove stale secondaryOk=true requirement from getMore section

The getMore section stated "The query flags passed to OP_QUERY for a
getMore command MUST be secondaryOk=true when sent to a secondary."

This contradicted the "Interactions with OP_QUERY" section which stated
"secondaryOk SHOULD not be set for follow-up getMore and killCursors
commands."

Commit 1aabad4 (2015-10-17) reversed the original 2015-09-30 decision
and updated the spec body and changelog accordingly, but missed this
sentence in the getMore section. Remove it to align with the SHOULD NOT
rule that has been in effect since 2015-10-13.

Author: GromNaN

source/find_getmore_killcursors_commands/find_getmore_killcursors_commands.md

@@ -264,8 +264,7 @@ to the value of the option **maxAwaitTimeMS**. If no **maxAwaitTimeMS** is speci
 ### getMore
 
 The [getMore](https://www.mongodb.com/docs/manual/reference/command/getMore/) command replaces the **OP_GET_MORE** wire
-protocol message. The query flags passed to OP_QUERY for a getMore command MUST be secondaryOk=true when sent to a
-secondary. The OP_QUERY namespace MUST be the same as for the **find** and **killCursors** commands.
+protocol message. The OP_QUERY namespace MUST be the same as for the **find** and **killCursors** commands.
 
 ```typescript
 interface GetMoreCommand {
@@ -456,6 +455,8 @@ More in depth information about passing read preferences to Mongos can be found
 
 ## Changelog
 
+- 2026-05-13: Remove stale `secondaryOk=true` requirement from getMore section.
+
 - 2024-07-30: Migrated from reStructuredText to Markdown.
 
 - 2023-05-10: Improve tailable cursor description and update the `getMore` section code blocks.