test: exploreUtils (#13719)

* Tests for exploreUtils

* removing eslint-disable

* applying factory

* Removing skip tests and code comments.

* Improving test name

* remove comments

* Improving "shouldUseLegacyApi" tests

* fixing typo

superset-frontend/src/explore/exploreUtils/getChartKey.test.ts

@@ -0,0 +1,23 @@
+/**
+ * Licensed to the Apache Software Foundation (ASF) under one
+ * or more contributor license agreements.  See the NOTICE file
+ * distributed with this work for additional information
+ * regarding copyright ownership.  The ASF licenses this file
+ * to you under the Apache License, Version 2.0 (the
+ * "License"); you may not use this file except in compliance
+ * with the License.  You may obtain a copy of the License at
+ *
+ *   http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing,
+ * software distributed under the License is distributed on an
+ * "AS IS" BASIS, WITHOUT WARRANTIES OR CONDITIONS OF ANY
+ * KIND, either express or implied.  See the License for the
+ * specific language governing permissions and limitations
+ * under the License.
+ */
+import { getChartKey } from '.';
+
+test('should return "slice_id" when called with an object that has "slice.slice_id"', () => {
+  expect(getChartKey({ slice: { slice_id: 100 } })).toBe(100);
+});