docs(types): fix icon_button type in jsdoc description to be icon_button (#2380)

Author: lukegalbraithrussell

packages/types/src/block-kit/block-elements.ts

@@ -212,7 +212,7 @@ export interface FileInput extends Actionable {
  */
 export interface IconButton extends Actionable, Confirmable {
   /**
-   * @description The type of element. In this case `type` is always `file_input`.
+   * @description The type of element. In this case `type` is always `icon_button`.
    */
   type: 'icon_button';
   /**