add see also link (#3489)

* add see also link

* fix broken link

Author: mairaw

xml/System.Net/SecurityProtocolType.xml

@@ -42,6 +42,7 @@ The Transport Layer Security (TLS) protocols assume that a connection-oriented p
 
  ]]></format>
     </remarks>
+    <related type="Article" href="~/docs/framework/network-programming/tls.md">Transport Layer Security (TLS) best practices with the .NET Framework</related>
   </Docs>
   <Members>
     <Member MemberName="Ssl3">