typeahead: Fix typeahead position not updating on pill remove.

Calls popper instance update method to refresh the position
of the typeahead menu.

web/src/bootstrap_typeahead.ts

@@ -505,7 +505,8 @@ export class Typeahead<ItemType extends string | object> {
             .on("keypress", this.keypress.bind(this))
             .on("keyup", this.keyup.bind(this))
             .on("click", this.element_click.bind(this))
-            .on("keydown", this.keydown.bind(this));
+            .on("keydown", this.keydown.bind(this))
+            .on("typeahead.refreshPosition", this.refreshPosition.bind(this));
 
         this.$menu
             .on("click", "li", this.click.bind(this))
@@ -736,6 +737,14 @@ export class Typeahead<ItemType extends string | object> {
         this.$menu.find(".active").removeClass("active");
         $(e.currentTarget).addClass("active");
     }
+
+    refreshPosition(e: JQuery.Event): void {
+        e.stopPropagation();
+        // Refresh the typeahead menu to account for any changes in the
+        // input position by asking popper to recompute your tooltip's position.
+        // eslint-disable-next-line @typescript-eslint/no-floating-promises
+        this.instance?.popperInstance?.update();
+    }
 }
 
 /* TYPEAHEAD PLUGIN DEFINITION

web/src/input_pill.ts

@@ -440,6 +440,9 @@ export function create<T>(opts: InputPillCreateOptions<T>): InputPillContainer<T
             const $next = $pill.next();
 
             funcs.removePill($pill[0]!);
+            // Since removing a pill moves the $input, typeahead needs to refresh
+            // to appear at the correct position.
+            store.$input.trigger(new $.Event("typeahead.refreshPosition"));
             $next.trigger("focus");
         });