Block Editor: Remove leftover files

packages/block-editor/CHANGELOG.md

@@ -2,6 +2,10 @@
 
 ## Unreleased
 
+### Breaking Changes
+
+-   Remove `src/default-editor-styles.scss`. Consumers importing it should supply their own ([#81793](https://github.com/WordPress/gutenberg/pull/81793)).
+
 ### New Features
 
 -   Register and handle the keyboard shortcuts that blocks declare on their variations and transforms, so that any block can contribute a shortcut without the editor knowing about it. Shortcuts apply to the selected block, and are listed under "Block shortcuts" in the keyboard shortcuts help modal ([#81588](https://github.com/WordPress/gutenberg/pull/81588)).