Add redirect for `/forms/`.

site/content/docs/4.3/forms/overview.md

@@ -4,6 +4,7 @@ title: Forms
 description: Examples and usage guidelines for form control styles, layout options, and custom components for creating a wide variety of forms.
 group: forms
 toc: true
+aliases: "/docs/4.3/forms/"
 sections:
   - title: Form control
     description: Style textual inputs and textareas with support for multiple states.