Add support for privacy-enhanced youtube to video shortcode

[cderv]

Discussed in #4050

^{Originally posted by jmgirard January 22, 2023}
When you share a video from youtube with "privacy-enhanced mode" enabled, the link will be youtube-nocookie.com instead of youtube.com. It would be great to support this in the video shortcode:

{{< video https://www.youtube-nocookie.com/embed/mrvhj2XUfWo >}}

Currently (v1.3.124), you get a "No compatible source was found for this media" error.

[cderv]

For context, this error comes from Video.js (https://github.com/videojs/video.js) itself which is used for Video feature in Quarto
Complete error is

VIDEOJS: ERROR: (CODE:4 MEDIA_ERR_SRC_NOT_SUPPORTED) No compatible source was found for this media.

FWIW going to the url of the video shows no video to me, but still can't show this other video https://www.youtube-nocookie.com/embed/wo9vZccmqwc

video.js does not work with those urls out of the box - It requires plugins. it seems another layer on video.js is required called videojs-youtube, specific for YouTube link.

But it seems we don't use that for Youtube anyway, and directly create the embed code.

quarto-cli/src/resources/extensions/quarto/video/video.lua

Lines 67 to 93 in cc21e35

	local youTubeBuilder = function(params)
	if not (params and params.src) then return nil end
	local src = params.src
	match = checkEndMatch(src, 'https://www.youtube.com/embed/')
	match = match or checkEndMatch(src, 'https://youtu.be/')
	match = match or string.match(src, '%?v=(.-)&')
	match = match or string.match(src, '%?v=(.-)$')
	if not match then return nil end
	local YOUTUBE_EMBED = 'https://www.youtube.com/embed/'
	params.src = YOUTUBE_EMBED .. match
	local SNIPPET = [[<iframe data-external="1" src="{src}{start}"{width}{height} title="{title}" frameborder="0" allow="accelerometer; autoplay; clipboard-write; encrypted-media; gyroscope; picture-in-picture" allowfullscreen></iframe>]]
	snippet = replaceCommonAttributes(SNIPPET, params)
	local result = {}
	result.snippet = interpolate {
	snippet,
	start = params.start and '?start=' .. params.start or ''
	}
	result.type = VIDEO_TYPES.YOUTUBE
	result.src = params.src
	return result
	end

So we should probably add support there