Remove remnant comments from sass (opensearch-project#8500)

Signed-off-by: Fanit Kolchina <[email protected]>

Author: kolchfa-aws

_sass/color_schemes/opensearch.scss

@@ -76,12 +76,6 @@ $btn-primary-color: $purple-300;
 $base-button-color: $grey-lt-300;
 $table-border-color: $grey-lt-300;
 
-// $border-color: $grey-dk-200;
-// $search-result-preview-color: $grey-dk-000;
-// $search-background-color: $grey-dk-250;
-// $table-background-color: $grey-dk-250;
-// $feedback-color: darken($sidebar-color, 3%);
-
 $content-width: 740px;
 $max-content-width: 1080px;
 $top-button-margin: 48px;