docs: update docs icons (#12465)

### What problem does this PR solve?

Update icons for docs.
Trailing spaces are auto truncated by the editor, does not affect real
content.

### Type of change

- [x] Documentation Update

docs/develop/switch_doc_engine.md

@@ -1,6 +1,9 @@
 ---
 sidebar_position: 3
 slug: /switch_doc_engine
+sidebar_custom_props: {
+  categoryIcon: LucideShuffle
+}
 ---
 
 # Switch document engine