docs(component-testing): fix global component guide for vue 2 and 3 (#5111)

* docs(vue): fix global component guide

* docs: correct importing for vue 2 cypress

---------

Co-authored-by: Lachlan Miller <lachlan.miller.1990@outlook.com>

Author: huynl-96

docs/guides/component-testing/vue/examples.mdx

@@ -861,12 +861,11 @@ import Button from '../../src/components/Button.vue'
 
 Cypress.Commands.add('mount', (component, options = {}) => {
   // Setup options object
-  options.extensions = options.extensions || {}
-  options.extensions.plugins = options.extensions.plugins || []
-  options.extensions.components = options.extensions.components || {}
+  options.global = options.global || {}
+  options.global.components = options.global.components || {}
 
   // Register global components
-  options.extensions.components['Button'] = Button
+  options.global.components['Button'] = Button
 
   return mount(component, options)
 })
@@ -876,16 +875,16 @@ Cypress.Commands.add('mount', (component, options = {}) => {
 <TabItem value="Vue 2">
 
 ```js
-import { mount } from 'cypress/vue'
+import { mount } from 'cypress/vue2'
 import Button from '../../src/components/Button.vue'
 
 Cypress.Commands.add('mount', (component, options = {}) => {
   // Setup options object
-  options.global = options.global || {}
-  options.global.components = options.global.components || {}
+  options.extensions = options.extensions || {}
+  options.extensions.components = options.extensions.components || {}
 
   // Register global components
-  options.global.components['Button'] = Button
+  options.extensions.components['Button'] = Button
 
   return mount(component, options)
 })