Add YouTube CTL (#196)

* Start adding YouTube CTL

* Update messaging between YT CTL content scope and background

* Send event to trigger listener in surrogate to call onYouTubeIframeAPIReady()

* Vertically center block dialog content

* Use config sent to initCTL() to trigger CTP placeholders

* Update package-lock.json

* Add data-key=modal to modal element

* Update build/ files

* Update YT CTP flag

* Update YouTube entity from "Google LLC" to "Youtube" | Changed YT CTL flag back to "youtube-video"

* Use original embedded video size to set a fixed size to YT placeholders

* Update getSetting to getYoutubePreviewsEnabled

* Rollback initCTL(resp) to the original `resp` argument name

* Remove domains from embedded YT config

* Comment out Youtube embedded configuration while feature is not released

* Comment out imports for YT CTL while it is not released

Co-authored-by: francielefaccin <[email protected]>

Author: franfaccin