Fix broken specs

Fixes specs that got broken after some close buttons got converted from
plain button elements to GlButton components in GitLab UI.

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

-import { GlAlert, GlTable, GlEmptyState, GlIntersectionObserver, GlLoadingIcon } from '@gitlab/ui';
+import {
+  GlAlert,
+  GlTable,
+  GlEmptyState,
+  GlIntersectionObserver,
+  GlLoadingIcon,
+  GlButton,
+} from '@gitlab/ui';
 import { shallowMount } from '@vue/test-utils';
 import FirstClassGroupVulnerabilities from 'ee/security_dashboard/components/first_class_group_security_dashboard_vulnerabilities.vue';
 import VulnerabilityList from 'ee/security_dashboard/components/vulnerability_list.vue';
@@ -74,7 +81,7 @@ describe('First Class Group Dashboard Vulnerabilities Component', () => {
 
     it('should have an alert that is dismissable', () => {
       const alert = findAlert();
-      alert.find('button').trigger('click');
+      alert.find(GlButton).vm.$emit('click');
       return wrapper.vm.$nextTick(() => {
         expect(alert.exists()).toBe(false);
       });

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

-import { GlAlert, GlTable, GlEmptyState, GlIntersectionObserver, GlLoadingIcon } from '@gitlab/ui';
+import {
+  GlAlert,
+  GlButton,
+  GlTable,
+  GlEmptyState,
+  GlIntersectionObserver,
+  GlLoadingIcon,
+} from '@gitlab/ui';
 import { shallowMount, createLocalVue } from '@vue/test-utils';
 import Vuex from 'vuex';
 import FirstClassInstanceVulnerabilities from 'ee/security_dashboard/components/first_class_instance_security_dashboard_vulnerabilities.vue';
@@ -93,7 +100,7 @@ describe('First Class Instance Dashboard Vulnerabilities Component', () => {
 
     it('should have an alert that is dismissable', () => {
       const alert = findAlert();
-      alert.find('button').trigger('click');
+      alert.find(GlButton).vm.$emit('click');
       return wrapper.vm.$nextTick(() => {
         expect(alert.exists()).toBe(false);
       });

ee/spec/frontend/threat_monitoring/components/__snapshots__/network_policy_list_spec.js.snap

@@ -6,10 +6,10 @@ exports[`NetworkPolicyList component renders policies table 1`] = `
 <table
   aria-busy="false"
   aria-colcount="3"
-  aria-describedby="__BVID__333__caption_"
+  aria-describedby="__BVID__335__caption_"
   aria-multiselectable="false"
   class="table b-table gl-table table-hover b-table-stacked-md b-table-selectable b-table-select-single"
-  id="__BVID__333"
+  id="__BVID__335"
   role="table"
 >
   <!---->

spec/frontend/groups/components/invite_members_banner_spec.js

 import { shallowMount } from '@vue/test-utils';
-import { GlBanner } from '@gitlab/ui';
+import { GlBanner, GlButton } from '@gitlab/ui';
 import { mockTracking, unmockTracking } from 'helpers/tracking_helper';
 import { setCookie, parseBoolean } from '~/lib/utils/common_utils';
 import InviteMembersBanner from '~/groups/components/invite_members_banner.vue';
@@ -107,14 +107,12 @@ describe('InviteMembersBanner', () => {
   });
 
   describe('dismissing', () => {
-    const findButton = () => {
-      return wrapper.find('button');
-    };
+    const findButton = () => wrapper.findAll(GlButton).at(1);
 
     beforeEach(() => {
       wrapper = createComponent({ GlBanner });
 
-      findButton().trigger('click');
+      findButton().vm.$emit('click');
     });
 
     it('sets iDismissed to true', () => {

spec/frontend/static_site_editor/components/submit_changes_error_spec.js

@@ -19,7 +19,7 @@ describe('Submit Changes Error', () => {
     });
   };
 
-  const findRetryButton = () => wrapper.find(GlButton);
+  const findRetryButton = () => wrapper.findAll(GlButton).at(1);
   const findAlert = () => wrapper.find(GlAlert);
 
   beforeEach(() => {