fix broken frontend tests

spec/javascripts/commit/pipelines/pipelines_store_spec.js.es6

-require('~commit/pipelines/pipelines_store');
+require('~/commit/pipelines/pipelines_store');
 
 describe('Store', () => {
-  const store = gl.commits.pipelines.PipelinesStore;
+  let store;
 
   beforeEach(() => {
-    store.create();
+    store = new gl.commits.pipelines.PipelinesStore();
   });
 
   it('should start with a blank state', () => {
@@ -23,7 +23,7 @@ describe('Store', () => {
       },
     ];
 
-    store.store(pipelines);
+    store.storePipelines(pipelines);
 
     expect(store.state.pipelines.length).toBe(pipelines.length);
   });

spec/javascripts/vue_shared/components/pipelines_table_row_spec.js.es6

-/* global pipeline */
-
-require('~vue_shared/components/pipelines_table_row');
-require('./mock_data');
+require('~/vue_shared/components/pipelines_table_row');
+const pipeline = require('../../commit/pipelines/mock_data');
 
 describe('Pipelines Table Row', () => {
   let component;

spec/javascripts/vue_shared/components/pipelines_table_spec.js.es6

-/* global pipeline */
-
-require('~vue_shared/components/pipelines_table');
-require('~lib/utils/datetime_utility');
-require('./mock_data');
+require('~/vue_shared/components/pipelines_table');
+require('~/lib/utils/datetime_utility');
+pipeline = require('../../commit/pipelines/mock_data');
 
 describe('Pipelines Table', () => {
   preloadFixtures('static/environments/element.html.raw');