Fixed HTTPClient.xml:115 and 121 variant declaration

doc/classes/HTTPClient.xml

@@ -112,13 +112,13 @@
 				Generates a GET/POST application/x-www-form-urlencoded style query string from a provided dictionary, e.g.:
 				[codeblock]
 				var fields = {"username": "user", "password": "pass"}
-				String query_string = http_client.query_string_from_dict(fields)
+				var query_string = http_client.query_string_from_dict(fields)
 				# Returns "username=user&password=pass"
 				[/codeblock]
 				Furthermore, if a key has a [code]null[/code] value, only the key itself is added, without equal sign and value. If the value is an array, for each value in it a pair with the same key is added.
 				[codeblock]
 				var fields = {"single": 123, "not_valued": null, "multiple": [22, 33, 44]}
-				String query_string = http_client.query_string_from_dict(fields)
+				var query_string = http_client.query_string_from_dict(fields)
 				# Returns "single=123&not_valued&multiple=22&multiple=33&multiple=44"
 				[/codeblock]
 			</description>