Merge pull request #3976 from oswaldoacauan/fix-chat-max-message-length

bigbluebutton-html5/imports/ui/components/chat/component.jsx

bigbluebutton-html5/imports/ui/components/chat/container.jsx

...ml5/imports/ui/components/chat/message-form/component.jsx

...html5/imports/ui/components/chat/message-form/styles.scss

bigbluebutton-html5/imports/ui/components/chat/service.js

...on-html5/imports/ui/stylesheets/variables/typography.scss

bigbluebutton-html5/private/config/public/chat.yaml

bigbluebutton-html5/private/locales/en.json