chore: Move a11y violation tests to Playwright (#30293)

...account/featurePreview/AccountFeaturePreviewPage.spec.tsx

...s/account/omnichannel/OmnichannelPreferencesPage.spec.tsx

apps/meteor/client/views/admin/mailer/MailerPage.spec.tsx

.../views/omnichannel/currentChats/CurrentChatsPage.spec.tsx

apps/meteor/package.json

apps/meteor/tests/e2e/account-profile.spec.ts

apps/meteor/tests/e2e/administration.spec.ts

...r/tests/e2e/omnichannel/omnichannel-current-chats.spec.ts

apps/meteor/tests/e2e/utils/test.ts

yarn.lock