Fixed bad references to JsonReaderException (#2856)

Author: Ron Petrusha

xml/System.Text.Json/JsonCommentHandling.xml

@@ -54,7 +54,7 @@
       </ReturnValue>
       <MemberValue>0</MemberValue>
       <Docs>
-        <summary>Doesn't allow comments within the JSON input. Comments are treated as invalid JSON if found, and a <see cref="T:System.Text.Json.JsonReaderException" /> is thrown. This is the default value.</summary>
+        <summary>Doesn't allow comments within the JSON input. Comments are treated as invalid JSON if found, and a <see cref="T:System.Text.Json.JsonException" /> is thrown. This is the default value.</summary>
       </Docs>
     </Member>
     <Member MemberName="Skip">

xml/System.Text.Json/JsonReaderOptions.xml

@@ -82,7 +82,7 @@ By default, this property is set to `false`, and a <xref:System.Text.Json.JsonEx
 
 ## Remarks
 
-By default, the reader throws a <xref:System.Text.Json.JsonReaderException> if it encounters a comment.
+By default, the reader throws a <xref:System.Text.Json.JsonException> if it encounters a comment.
 
  ]]></format>
         </remarks>

xml/System.Text.Json/Utf8JsonReader.xml

@@ -28,7 +28,7 @@
 
 `Utf8JsonReader` processes the text sequentially with no caching and by default adheres strictly to the [JSON RFC](https://tools.ietf.org/html/rfc8259).
 
-When `Utf8JsonReader` encounters invalid JSON, it throws a <xref:System.Text.Json.JsonReaderException>  with basic error information like line number and byte position on the line.
+When `Utf8JsonReader` encounters invalid JSON, it throws a <xref:System.Text.Json.JsonException>  with basic error information like line number and byte position on the line.
 
 Since this type is a ref struct, it doesn't directly support async. However, it does provide support for reentrancy to read incomplete data and to continue reading once more data is presented.