Delete css.properties.line-height-step key removed from BCD

Author: ddbeck

features/rhythmic-sizing.yml

@@ -2,5 +2,3 @@ name: Rhythmic sizing
 description: The `line-height-step` CSS property creates consistent vertical rhythm by setting the spacing between body text baselines. It rounds taller lines like headings up to the next multiple of the body text spacing.
 spec: https://drafts.csswg.org/css-rhythm-1/
 group: text
-compat_features:
-  - css.properties.line-height-step

features/rhythmic-sizing.yml.dist

@@ -4,5 +4,3 @@
 status:
   baseline: false
   support: {}
-compat_features:
-  - css.properties.line-height-step