Fix Video Unavailable problem at YouTube preview

[Sn-Kinos]

Summary

Fixed the problem that YouTube preview shows Video Unavailable instead of the video.

• Added the properties on the iframe for YouTube preview at youtube_video.tsx

Reproduce

Create a post that occurs Video Unavailable problem. I used https://youtu.be/edsx_MOhVnk on the below screenshots.

Ticket Link

No Tickets. (less than 20 lines of code change)

Screenshots

I haven't change the UI. But I can show about it w/ screenshots.

before	after

Release Note

Fixed the problem that YouTube preview shows Video Unavailable instead of the video.

[mattermost-build]

Hello @Sn-Kinos,

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[pvev]

hey @Sn-Kinos , thank you for your contribution. Could you please describe the exact steps on how to reproduce the issue you are trying to solve so we can create a ticket and associate it with this fix? Thanks!

[Sn-Kinos]

hey @Sn-Kinos , thank you for your contribution. Could you please describe the exact steps on how to reproduce the issue you are trying to solve so we can create a ticket and associate it with this fix? Thanks!

Thanks @pvev! I added the reproduce section on the text :D