Make text-box-trim a draft feature

Author: foolip

feature-group-definitions/text-box-trim.yml

@@ -1,3 +1,6 @@
+# TODO: Publish when supported by some browser.
+draft: true
+draft_date: 2024-04-30
 name: text-box-trim
 description: The `text-box-trim` CSS property removes the additional space above and below text which is normally reserved for ascenders and descenders.
 spec: https://drafts.csswg.org/css-inline-3/#leading-trim