Update setup.scss

Author: KristinaYFischer

docs/_sass/custom/setup.scss

@@ -98,8 +98,8 @@ $gutter-spacing: $sp-6 !default;
 $gutter-spacing-sm: $sp-4 !default;
 $nav-width: 12rem;
 $nav-width-md: 11.5rem;
-$nav-list-item-height: $sp-6 !default;
-$nav-list-item-height-sm: $sp-8 !default;
+$nav-list-item-height: $sp-8;
+$nav-list-item-height-sm: $sp-9;
 $nav-list-expander-right: false;
 $content-width: 50rem !default;
 $header-height: 10rem;