Remove incorrect localVue usage

localVue is required only with use method

ee/spec/frontend/security_configuration/components/app_spec.js

-import { shallowMount, createLocalVue } from '@vue/test-utils';
+import { shallowMount } from '@vue/test-utils';
 
 import { GlLink } from '@gitlab/ui';
 import SecurityConfigurationApp from 'ee/security_configuration/components/app.vue';
 
-const localVue = createLocalVue();
-
 describe('Security Configuration App', () => {
   let wrapper;
   const createComponent = (props = {}) => {
     wrapper = shallowMount(SecurityConfigurationApp, {
-      localVue,
       propsData: {
         features: [],
         autoDevopsEnabled: false,

ee/spec/frontend/security_dashboard/components/app_spec.js

-import { shallowMount, createLocalVue } from '@vue/test-utils';
+import { shallowMount } from '@vue/test-utils';
 import MockAdapter from 'axios-mock-adapter';
 import { TEST_HOST } from 'helpers/test_constants';
 
@@ -13,8 +13,6 @@ import createStore from 'ee/security_dashboard/store';
 import { getParameterValues } from '~/lib/utils/url_utility';
 import axios from '~/lib/utils/axios_utils';
 
-const localVue = createLocalVue();
-
 const pipelineId = 123;
 const vulnerabilitiesEndpoint = `${TEST_HOST}/vulnerabilities`;
 const vulnerabilitiesCountEndpoint = `${TEST_HOST}/vulnerabilities_summary`;
@@ -41,7 +39,6 @@ describe('Security Dashboard app', () => {
   const createComponent = props => {
     store = createStore();
     wrapper = shallowMount(SecurityDashboardApp, {
-      localVue,
       store,
       sync: false,
       methods: {
@@ -104,7 +101,7 @@ describe('Security Dashboard app', () => {
       const newCount = 3;
 
       beforeEach(() => {
-        localVue.set(store.state.vulnerabilities.pageInfo, 'total', newCount);
+        store.state.vulnerabilities.pageInfo = { total: newCount };
       });
 
       it('emits a vulnerabilitiesCountChanged event', () => {

ee/spec/frontend/security_dashboard/components/project_list_spec.js

-import { shallowMount, createLocalVue } from '@vue/test-utils';
+import { shallowMount } from '@vue/test-utils';
 
 import { GlBadge, GlButton, GlLoadingIcon } from '@gitlab/ui';
 import ProjectList from 'ee/security_dashboard/components/project_list.vue';
 import ProjectAvatar from '~/vue_shared/components/project_avatar/default.vue';
 
-const localVue = createLocalVue();
-
 const getArrayWithLength = n => [...Array(n).keys()];
 const generateMockProjects = (projectsCount, mockProject = {}) =>
   getArrayWithLength(projectsCount).map(id => ({ id, ...mockProject }));
@@ -16,7 +14,6 @@ describe('Project List component', () => {
   const factory = ({ projects = [], stubs = {}, showLoadingIndicator = false } = {}) => {
     wrapper = shallowMount(ProjectList, {
       stubs,
-      localVue,
       propsData: {
         projects,
         showLoadingIndicator,