Update the TikTok embed handler to use amp-tiktok component

[pierlon]

Feature description

Now that ampproject/amphtml#32651 has been merged we can begin the process of updating AMP_TikTok_Embed_Handler to use the amp-tiktok component instead of amp-embedly-card.

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Acceptance criteria

• Inserting a TikTok embed should result in the amp-tiktok component being used on the AMP page.

Implementation brief

• Update the AMP_TikTok_Embed_Handler to use the amp-tiktok component rather than the amp-embedly-card one.

QA testing instructions

Demo

Changelog entry

[westonruter]

Looks like we're still waiting on ampproject/amphtml#32219 to be closed. The validator spec hasn't yet been updated.

[westonruter]

This can now be worked on as a PR off of #6436.

[westonruter]

This can now be worked on as a PR off of #6436.

The PR has been merged into develop. This work can proceed.

[delawski]

QA Passed

I've pasted a TikTok link into a post that got automatically converted into an embed. I've then visited the AMP version of the post and confirmed that - as expected - the amp-tiktok element has been used to render the embed:

Tested against Version 2.2.0-alpha-20210825T212353Z-ab5a1e7

[westonruter]

(To re-check on 2.1.4)

[westonruter]

I've fixed the 2.1 build errors via #6574. That should allow a new 2.1 branch build to be created, although there is a JS unit test error still. See #6235 (comment).

[delawski]

Confirmed to be working as expected on 2.1.4-alpha: