Prevent splitting of textarea's closing tag

[t-mangoe]

Description

This PR fixes the issue #15432

Fix #15432

Checklist

• I’ve added tests to confirm my change works.
• (If changing the API or CLI) I’ve documented the changes I’ve made (in the docs/ directory).
• (If the change is user-facing) I’ve added my changes to changelog_unreleased/*/XXXX.md file following changelog_unreleased/TEMPLATE.md.
• I’ve read the contributing guidelines.

✨Try the playground for this PR✨

[drewble]

Can this fix be merged? Without it, formatting rules are inconsistently applied across HTML elements and the post-Prettier file looks broken.

[fisker]

Sorry, this will break html, we can't accept it.

<textarea id="a">a</textarea
>

<textarea id="b">a
</textarea>

<script>
  alert(a.value === b.value);
</script>

[jacobtylerwalls]

The underlying issue also affects the <span> tag, see playground