Remove BS4 reference

Author: ericgio

src/components/Typeahead/Typeahead.tsx

@@ -52,15 +52,15 @@ export interface TypeaheadComponentProps extends Partial<TypeaheadProps> {
   emptyLabel?: ReactNode;
   flip?: boolean;
   /**
-   * Bootstrap 4 only. Adds the `is-invalid` classname to the `form-control`.
+   * Adds the `is-invalid` classname to the `form-control`.
    */
   isInvalid?: boolean;
   /**
    * Indicate whether an asynchronous data fetch is happening.
    */
   isLoading?: boolean;
   /**
-   * Bootstrap 4 only. Adds the `is-valid` classname to the `form-control`.
+   * Adds the `is-valid` classname to the `form-control`.
    */
   isValid?: boolean;
   maxHeight?: string;