Remove incorrect localVue usage

localVue is required only with use method

ee/spec/frontend/approvals/components/approval_check_popover_spec.js

 import Vue from 'vue';
-import { shallowMount, createLocalVue } from '@vue/test-utils';
+import { shallowMount } from '@vue/test-utils';
 import { GlPopover, GlLink } from '@gitlab/ui';
 import { TEST_HOST } from 'helpers/test_constants';
 import component from 'ee/approvals/components/approval_check_popover.vue';
 
-const localVue = createLocalVue();
-
 describe('Approval Check Popover', () => {
   let wrapper;
 
   beforeEach(() => {
     wrapper = shallowMount(component, {
-      localVue,
       propsData: {
         title: 'Title',
       },

ee/spec/frontend/approvals/components/approval_check_rule_popover_spec.js

 import Vue from 'vue';
-import { shallowMount, createLocalVue } from '@vue/test-utils';
+import { shallowMount } from '@vue/test-utils';
 import { TEST_HOST } from 'helpers/test_constants';
 import component from 'ee/approvals/components/approval_check_rule_popover.vue';
 import {
@@ -12,9 +12,7 @@ describe('Approval Check Popover', () => {
   let wrapper;
 
   beforeEach(() => {
-    const localVue = createLocalVue();
     wrapper = shallowMount(component, {
-      localVue,
       propsData: { rule: {} },
       sync: false,
     });

ee/spec/frontend/approvals/components/approvers_list_item_spec.js

-import { shallowMount, createLocalVue } from '@vue/test-utils';
+import { shallowMount } from '@vue/test-utils';
 import { GlButton } from '@gitlab/ui';
 import { TYPE_USER, TYPE_GROUP, TYPE_HIDDEN_GROUPS } from 'ee/approvals/constants';
 import ApproversListItem from 'ee/approvals/components/approvers_list_item.vue';
 import HiddenGroupsItem from 'ee/approvals/components/hidden_groups_item.vue';
 import Avatar from '~/vue_shared/components/project_avatar/default.vue';
 
-const localVue = createLocalVue();
 const TEST_USER = {
   id: 1,
   type: TYPE_USER,
@@ -22,9 +21,8 @@ describe('Approvals ApproversListItem', () => {
   let wrapper;
 
   const factory = (options = {}) => {
-    wrapper = shallowMount(localVue.extend(ApproversListItem), {
+    wrapper = shallowMount(ApproversListItem, {
       ...options,
-      localVue,
       sync: false,
     });
   };

ee/spec/frontend/approvals/components/approvers_list_spec.js

-import { shallowMount, createLocalVue } from '@vue/test-utils';
+import { shallowMount } from '@vue/test-utils';
 import ApproversListEmpty from 'ee/approvals/components/approvers_list_empty.vue';
 import ApproversListItem from 'ee/approvals/components/approvers_list_item.vue';
 import ApproversList from 'ee/approvals/components/approvers_list.vue';
 import { TYPE_USER, TYPE_GROUP } from 'ee/approvals/constants';
 
-const localVue = createLocalVue();
 const TEST_APPROVERS = [
   { id: 1, type: TYPE_GROUP },
   { id: 1, type: TYPE_USER },
@@ -16,9 +15,8 @@ describe('ApproversList', () => {
   let wrapper;
 
   const factory = (options = {}) => {
-    wrapper = shallowMount(localVue.extend(ApproversList), {
+    wrapper = shallowMount(ApproversList, {
       ...options,
-      localVue,
       propsData,
     });
   };