Fix Video Unavailable problem at YouTube preview (#26980)

* Fix YouTube preview shows Video Unavailable

* Fix typo on iframe property

* Remove duplicated property

* fix lint error (double-quotes, unknown property)

* renew snapshot for youtube_video.tsx

* fix double quotes and newline error on snapshot for youtube_video.tsx

* fix blank on snapshot for youtube_video.tsx

* Add YouTube Shorts Embed Preview

* Revert "Add YouTube Shorts Embed Preview"

This reverts commit b5fb7a4076ef73774a0e50157f371516b9d383b2.

* Add setting for Youtube Referrer Policy

* fix test code error about Youtube Referrer Policy

* remove mistake changes on `webpack.config.js`

* add test and snapshot about `youtubeReferrerPolicy = true`

* fix errors on ci

* update description of YouTube Referrer Policy

* remove unnecessary whitespace in default_config.ts

* remove ko.json changes to prevent conflict with translate tool

* update snapshot of `youtube_video.test.tsx`

* referrerPolicy on `youtube_video` didn't follow global policy value

https://github.com/mattermost/mattermost/pull/26980#discussion_r1672524152

* update snapshot of `youtube_video.test.tsx`

* Remove obsolete snapshot

* fix typo on index.ts @ youtube_video

---------

Co-authored-by: Mattermost Build <build@mattermost.com>
Co-authored-by: Harrison Healey <harrisonmhealey@gmail.com>

server/platform/services/telemetry/telemetry.go

@@ -778,6 +778,7 @@ func (ts *TelemetryService) trackConfig() {
 		"enable_app_bar":                      !*cfg.ExperimentalSettings.DisableAppBar,
 		"disable_refetching_on_browser_focus": *cfg.ExperimentalSettings.DisableRefetchingOnBrowserFocus,
 		"delay_channel_autocomplete":          *cfg.ExperimentalSettings.DelayChannelAutocomplete,
+		"youtube_referrer_policy":             *cfg.ExperimentalSettings.YoutubeReferrerPolicy,
 	})
 
 	ts.SendTelemetry(TrackConfigAnalytics, map[string]any{