Update Twitter shortcode oEmbed endpoint

Update Twitter shortcode oEmbed endpoint

The existing endpoint will be retired and removed on November 23, 2021.
References:

- https://twittercommunity.com/t/consolidating-the-oembed-functionality/154690
- https://developer.twitter.com/en/docs/twitter-for-websites/oembed-api#Embedded

This is a backward compatible change.

The existing endpoint requires a single parameter: the id of the tweet.

The new endpoint requires two parameters: the id of the tweet, and the
user with whom it is associated. For the moment, if you supply the wrong
user, the request will be redirected (with a small delay) to the correct
user/id pair. This behavior is undocumented, but we will take advantage
of it as Hugo site authors transition to the new syntax.

{{< tweet 1453110110599868418 >}} --> works, throws warning, deprecate at some point

{{< tweet user="SanDiegoZoo" id="1453110110599868418" >}} --> new syntax

Fixes #8130