[css-nesting-1][editorial] Fixed Bikeshed issue

Author: SebastianZ

css-nesting-1/Overview.bs

@@ -10,6 +10,7 @@ TR: https://www.w3.org/TR/css-nesting-1/
 Editor: Tab Atkins-Bittner, Google, http://xanthir.com/contact/, w3cid 42199
 Former Editor: Adam Argyle, Google, https://nerdy.dev, w3cid 112669
 Abstract: This module introduces the ability to nest one style rule inside another, with the selector of the child rule relative to the selector of the parent rule.  This increases the modularity and maintainability of CSS stylesheets.
+Ignored Terms: cssText
 Default Highlight: css
 Include MDN Panels: no
 WPT Path Prefix: css/css-nesting/