Autocomplete: remove duplicate prop in types (#11388)

Author: Leopoldthecoder

types/autocomplete.d.ts

@@ -56,9 +56,6 @@ export declare class ElAutocomplete extends ElementUIComponent {
   /** Whether show suggestions when input focus */
   triggerOnFocus: boolean
 
-  /** Whether to emit a `select` event on enter when there is no autocomplete match */
-  selectWhenUnmatched: boolean
-
   /** Prefix icon class */
   prefixIcon: string