doc: fix introduced_in note in querystring.md

The method descriptions mentioned the right version but for some reason
the top-level description did not. Well, now it does.

PR-URL: #29014
Reviewed-By: Colin Ihrig <cjihrig@gmail.com>
Reviewed-By: Trivikram Kamat <trivikr.dev@gmail.com>
Reviewed-By: Luigi Pinca <luigipinca@gmail.com>
Reviewed-By: James M Snell <jasnell@gmail.com>

doc/api/querystring.md

@@ -1,6 +1,6 @@
 # Query String
 
-<!--introduced_in=v0.10.0-->
+<!--introduced_in=v0.1.25-->
 
 > Stability: 2 - Stable