Fix return documentation to reference correct class names

- Fixed JsonArray.xml to reference JsonArray instead of JsonValue
- Fixed JsonObject.xml to reference JsonObject instead of JsonValue

Co-authored-by: GrantMeStrength <1928855+GrantMeStrength@users.noreply.github.com>

Author: Copilot

winrt-api-build/xml/Windows.Data.Json/JsonArray.xml

@@ -19,7 +19,7 @@
         <param name="input">The specified string.</param>
         <param name="result">The new JsonArray object.</param>
         <summary>Parses the provided string into a JsonArray.</summary>
-        <returns>True if the JsonValue object was successfully created; otherwise, false.</returns>
+        <returns>True if the JsonArray object was successfully created; otherwise, false.</returns>
       </Docs>
     </Member>
   </Members>

winrt-api-build/xml/Windows.Data.Json/JsonObject.xml

@@ -19,7 +19,7 @@
         <param name="input">The specified JSON string.</param>
         <param name="result">The resultant JsonObject.</param>
         <summary>Parses the specified string that represents a JSON object into a JsonObject.</summary>
-        <returns>True if the JsonValue object was successfully created; otherwise, false.</returns>
+        <returns>True if the JsonObject object was successfully created; otherwise, false.</returns>
       </Docs>
     </Member>
   </Members>