embedded iframes are generated with the wrong css class

[mco-gh]

@Mrc0113 13 says...
I think there may be an issue where the iframes that aren't youtube videos are still labeled as the class="youtube-video" instead of the other one that was added.

Generated code from your example:

<iframe class="youtube-video" src="https://repl.it/@marcacohen/FrigidVacantAdmins?lite=true"></iframe>

Marc C says...
Thanks Marc! PR approved. The embedded-iframe class is identically defined with the youtube-video class so there's no functional problem but I agree it can cause confusion to anyone perusing the generated artifacts. I've fixed this in a private repo but I need to update the distributed css first to avoid breakage and there seems to be a problem with the latter. I'm gonna dump this conversation into a repo issue and when the css distro gets fixed, I'll submit this PR.

[mco-gh]

css distro updated, this PR can go ahead