fix exception links (dotnet#3174)

Author: mairaw

xml/System.Text.Json/JsonSerializerOptions.xml

@@ -59,7 +59,7 @@
 
 ## Remarks
 
-By default, `AllowTrailingCommas` is set to `false`, and a <exception cref="T:System.Text.Json.JsonException> is thrown if a trailing comma is encountered.
+By default, `AllowTrailingCommas` is set to `false`, and a <xref:System.Text.Json.JsonException> is thrown during deserialization if a trailing comma is encountered.
 
           ]]></format>
         </remarks>
@@ -284,7 +284,7 @@ Read-only properties are not deserialized regardless of this setting.
 
 ## Remarks
 
-Going past this depth will throw a <exception cref="T:System.Text.Json.JsonException>.
+Going past this depth throws a <xref:System.Text.Json.JsonException>.
 
           ]]></format>
         </remarks>
@@ -378,7 +378,7 @@ This property can be set to <xref:System.Text.Json.JsonNamingPolicy.CamelCase?di
 
 ## Remarks
 
-By default, a <exception cref="T:System.Text.Json.JsonException> is thrown if a comment is encountered.
+By default, a <xref:System.Text.Json.JsonException> is thrown during deserialization if a comment is encountered.
 
           ]]></format>
         </remarks>