It was already pointed out that you have an invalid
</blockquote> tag, have you resolved that issue? You need to include the opening (and matching)
<blockquote> from publish.twitter.com for the correct class to be applied to the Tweet embed.
<blockquote class="twitter-tweet"><p lang="en" dir="ltr">Big vote tomorrow in the House. Tax cuts are getting close!</p>— Donald J. Trump (@realDonaldTrump) <a href="https://twitter.com/realDonaldTrump/status/930982399202217984?ref_src=twsrc%5Etfw">November 16, 2017</a></blockquote> <script async src="https://platform.twitter.com/widgets.js" charset="utf-8"></script>