Fix typo.

packages/block-library/src/navigation/editor.scss

@@ -290,8 +290,8 @@ $color-control-label-height: 20px;
 
 // Selected "Start empty" state.
 // In this state, the block is entirely empty and will collapse to zero height unless there's
-// content inside. The below rule lets the placeholder staty in an invisible state to avoid
-// collapse and layout shift.
+// content inside. The below rule lets the placeholder stay in an invisible state to avoid
+// collapsing and shifting the layout.
 // @todo: This fix could be augmented with showing the generic appender when there are no
 // innerblocks, a la how the Row block does it.
 .wp-block-navigation.is-selected .wp-block-navigation__container .wp-block-navigation-placeholder__preview:first-of-type {