Fix EmberArray.uniqBy typing (#25073)

types/ember/index.d.ts

@@ -1243,7 +1243,7 @@ declare module 'ember' {
              * Returns a new enumerable that contains only items containing a unique property value.
              * The default implementation returns an array regardless of the receiver type.
              */
-            uniqBy(): NativeArray<T>;
+            uniqBy(property: string): NativeArray<T>;
             /**
              * Returns `true` if the passed object can be found in the enumerable.
              */

types/ember/test/array-ext.ts

@@ -16,3 +16,6 @@ assertType<number>(array.get('length'));
 assertType<Person | undefined>(array.get('firstObject'));
 assertType<string[]>(array.mapBy('name'));
 assertType<string[]>(array.map(p => p.get('name')));
+assertType<Person[]>(array.sortBy('name'));
+assertType<Person[]>(array.uniq());
+assertType<Person[]>(array.uniqBy('name'));