fix link

Architecture.md

@@ -57,7 +57,7 @@ For this, you'll have to implement the `BaseRequest` interface class and pass tw
 ### Update handlers
 
 The `Handler` interface class is the most import class when it comes to the question of how the `Application` processes updates.
-PTB comes with a number of [[built-in handler|Types-of-Handler]] which cover most important use cases.
+PTB comes with a number of [[built-in handler|Types-of-Handlers]] which cover most important use cases.
 However, if you want to implement a custom logic of when an update should be handled, you can also write a custom implementation of `Handler` and use that.
 
 ### Persistence