Add change note + fix qldoc

Author: joefarebrother

csharp/ql/lib/semmle/code/csharp/frameworks/Razor.qll

@@ -222,7 +222,7 @@ class PageModelClass extends Class {
     this.getABaseType+().hasFullyQualifiedName("Microsoft.AspNetCore.Mvc.RazorPages", "PageModel")
   }
 
-  /** A handler method such as `OnGetAsync` */
+  /** Gets a handler method such as `OnGetAsync` */
   Method getAHandlerMethod() {
     result = this.getAMethod() and
     result.getName().matches("On%") and

csharp/ql/src/change-notes/2023-12-12-page-model-flow-steps.md

@@ -0,0 +1,4 @@
+---
+category: minorAnalysis
+---
+* Modelled additional flow steps to track flow from handler methods of a `PageModel` class to the corresponding Razor Page (`.cshtml`) file, which may result in additional results for queries such as `cs/web/xss`.