Fix defaultCredentialsHandleCacheSize docs (#4383)

* Fix defaultCredentialsHandleCacheSize docs

The documentation for the `defaultCredentialsHandleCacheSize` setting is incorrect.

* Update xml/System.Net.Configuration/WindowsAuthenticationElement.xml

Co-authored-by: Genevieve Warren <[email protected]>

* Fix typo

Co-authored-by: Genevieve Warren <[email protected]>

Author: davidsh

xml/System.Net.Configuration/WindowsAuthenticationElement.xml

@@ -61,7 +61,7 @@
         <remarks>
           <format type="text/markdown"><![CDATA[  
 
-By default, Windows allocates a separate SSPI handle for each <xref:System.Net.HttpWebRequest>. If this behavior impacts performance, you can use the `DefaultCredentialsHandleCacheSize` to use a single cached SSPI credential handle for default network credentials. You can do this by setting this property value to 0. This corresponds to the following configuration setting:
+By default, the value of `defaultCredentialsHandleCacheSize` is 0. This causes Windows to allocate a separate SSPI handle for each <xref:System.Net.HttpWebRequest>.
 
 ```xml
 <system.net>
@@ -71,6 +71,8 @@ By default, Windows allocates a separate SSPI handle for each <xref:System.Net.H
 </system.net>
 ```
 
+If this behavior impacts performance, set <xref:System.Net.Configuration.WindowsAuthenticationElement.DefaultCredentialsHandleCacheSize> to a value greater than 0 to use a single, cached SSPI credential handle for default network credentials. The exact value depends on application requirements. Generally, a value between 50 and 100 works for most high-performant applications.
+
          ]]></format>
         </remarks>
       </Docs>