improving note on HTTPRequest class under the request method documentation

(cherry picked from commit 1ed3d9a0b0a0a69070af59eee4325f69c4302dc7)

doc/classes/HTTPRequest.xml

@@ -106,7 +106,7 @@
 			<description>
 				Creates request on the underlying [HTTPClient]. If there is no configuration errors, it tries to connect using [method HTTPClient.connect_to_host] and passes parameters onto [method HTTPClient.request].
 				Returns [constant OK] if request is successfully created. (Does not imply that the server has responded), [constant ERR_UNCONFIGURED] if not in the tree, [constant ERR_BUSY] if still processing previous request, [constant ERR_INVALID_PARAMETER] if given string is not a valid URL format, or [constant ERR_CANT_CONNECT] if not using thread and the [HTTPClient] cannot connect to host.
-				[b]Note:[/b] The [code]request_data[/code] parameter is ignored if [code]method[/code] is [constant HTTPClient.METHOD_GET]. This is because GET methods can't contain request data. As a workaround, you can pass request data as a query string in the URL. See [method String.http_escape] for an example.
+				[b]Note:[/b] When [code]method[/code] is [constant HTTPClient.METHOD_GET], the payload sent via [code]request_data[/code] might be ignored by the server or even cause the server to reject the request (check [url=https://datatracker.ietf.org/doc/html/rfc7231#section-4.3.1]RFC 7231 section 4.3.1[/url] for more details). As a workaround, you can send data as a query string in the URL. See [method String.http_escape] for an example.
 			</description>
 		</method>
 	</methods>