Update Zendesk links for new subdomain

ui/app/components/modals/confirm-remove-account/confirm-remove-account.component.js

@@ -78,7 +78,7 @@ export default class ConfirmRemoveAccount extends Component {
             <a
               className="confirm-remove-account__link"
               rel="noopener noreferrer"
-              target="_blank" href="https://consensys.zendesk.com/hc/en-us/articles/360004180111-What-are-imported-accounts-New-UI-">
+              target="_blank" href="https://metamask.zendesk.com/hc/en-us/articles/360015289932">
               { t('learnMore') }
             </a>
           </div>

ui/app/components/pages/add-token/token-list/token-list-placeholder/token-list-placeholder.component.js

@@ -15,7 +15,7 @@ export default class TokenListPlaceholder extends Component {
         </div>
         <a
           className="token-list-placeholder__link"
-          href="https://consensys.zendesk.com/hc/en-us/articles/360004135092"
+          href="https://metamask.zendesk.com/hc/en-us/articles/360015489031"
           target="_blank"
           rel="noopener noreferrer"
         >

ui/app/components/pages/create-account/import-account/index.js

@@ -46,7 +46,7 @@ AccountImportSubview.prototype.render = function () {
           },
           onClick: () => {
             global.platform.openWindow({
-              url: 'https://consensys.zendesk.com/hc/en-us/articles/360004180111-What-are-imported-accounts-New-UI',
+              url: 'https://metamask.zendesk.com/hc/en-us/articles/360015289932',
             })
           },
         }, this.context.t('here')),

ui/app/components/signature-request.js

@@ -204,7 +204,7 @@ SignatureRequest.prototype.renderBody = function () {
       h('span.request-signature__help-link', {
         onClick: () => {
           global.platform.openWindow({
-            url: 'https://consensys.zendesk.com/hc/en-us/articles/360004427792',
+            url: 'https://metamask.zendesk.com/hc/en-us/articles/360015488751',
           })
         },
     }, this.context.t('learnMore'))]