fix for issue #6682 / make poll panel resizable

.../ui/components/actions-bar/actions-dropdown/component.jsx

...n-html5/imports/ui/components/panel-manager/component.jsx

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

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

...tml5/imports/ui/components/poll/live-result/component.jsx

...-html5/imports/ui/components/poll/live-result/styles.scss

bigbluebutton-html5/imports/ui/components/poll/styles.scss

...ebutton-html5/imports/ui/components/polling/component.jsx

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

...luebutton-html5/imports/ui/components/polling/styles.scss