BaseInput: Only move focus if suggestion list is not visible

`! this.completer.hasSuggestions()` ensures that the suggestion list is not
visible, otherwise pressing ArrowDown or ArrowUp to select the suggested
options will change the focus of the terms. This will cause the selected
suggestion to overwrite the existing term at position 0.

Or if a term is being edited and something is selected from the suggestion list,
a new duplicate term is added because the focus has moved again.

asset/js/widget/BaseInput.js

@@ -791,15 +791,15 @@ define(["../notjQuery", "Completer"], function ($, Completer) {
                     break;
                 case 'ArrowUp':
                     if (this.isTermDirectionVertical() && this.hasTerms()
-                        && (this.completer === null || ! this.completer.isBeingCompleted(input))
+                        && (this.completer === null || ! this.completer.isBeingCompleted(input) && ! this.completer.hasSuggestions())
                     ) {
                         event.preventDefault();
                         this.moveFocusBackward();
                     }
                     break;
                 case 'ArrowDown':
                     if (this.isTermDirectionVertical() && this.hasTerms()
-                        && (this.completer === null || ! this.completer.isBeingCompleted(input))
+                        && (this.completer === null || ! this.completer.isBeingCompleted(input) && ! this.completer.hasSuggestions())
                     ) {
                         event.preventDefault();
                         this.moveFocusForward();