refactor(eslint): Add "no-floating-promises" eslint rule - Part 2 (#28464)

apps/meteor/app/api/server/v1/mailer.ts

apps/meteor/app/livechat/server/api/v1/contact.ts

.../server/application/room/sender/RoomServiceSender.spec.ts

apps/meteor/tests/data/livechat/rooms.ts

apps/meteor/tests/end-to-end/api/26-LDAP.ts

apps/meteor/tests/end-to-end/api/27-roles.ts

apps/meteor/tests/end-to-end/api/import.spec.ts

apps/meteor/tests/end-to-end/api/livechat/00-rooms.ts

apps/meteor/tests/end-to-end/api/livechat/01-agents.ts

apps/meteor/tests/end-to-end/api/livechat/02-appearance.ts

.../meteor/tests/end-to-end/api/livechat/03-custom-fields.ts

apps/meteor/tests/end-to-end/api/livechat/04-dashboards.ts

apps/meteor/tests/end-to-end/api/livechat/05-inquiries.ts

apps/meteor/tests/end-to-end/api/livechat/06-integrations.ts

apps/meteor/tests/end-to-end/api/livechat/07-queue.ts

apps/meteor/tests/end-to-end/api/livechat/08-triggers.ts

apps/meteor/tests/end-to-end/api/livechat/09-visitors.ts

apps/meteor/tests/end-to-end/api/livechat/10-departments.ts

apps/meteor/tests/end-to-end/api/livechat/11-email-inbox.ts

apps/meteor/tests/end-to-end/api/livechat/11-livechat.ts