docs: fix link in validation page (#3983)

docs/content/concepts/validation.mdx

@@ -74,4 +74,4 @@ React Hook Form is a library for managing form state and validation in React app
 
 With React Hook Form, you can easily manage form state without the need for controlled components, making your code cleaner and more concise. It also offers performance benefits by reducing unnecessary re-renders.
 
-For some examples have a look at [Building Forms](/concepts/building-forms#handling-complex-forms-and-form-state) section.
+For some examples have a look at [Building Forms](/patterns/building-forms#handling-complex-forms-and-form-state) section.