migrate newly introduced colors

Author: VasilyStrelyaev

packages/devextreme-scss/scss/widgets/fluent/chat/_colors.scss

@@ -141,7 +141,7 @@ $chat-file-secondary-color: null !default;
   $chat-typingindicator-circle-bg-color-center: color.adjust($base-bg, $lightness: -56.08%, $space: hsl) !default;
 
   $chat-file-container-box-shadow: 0 0 2px 0 color.change($base-shadow-color, $alpha: 0.12), 0 1px 2px 0 color.change($base-shadow-color, $alpha: 0.14) !default;
-  $chat-file-secondary-color: lighten($base-text-color, 29.80) !default;
+  $chat-file-secondary-color: color.adjust($base-text-color, $lightness: 29.80%, $space: hsl) !default;
 
   @if $color == "blue" {
     $chat-bubble-background-color-primary: color.adjust($base-accent, $hue: 3.8deg, $saturation: -11.4%, $lightness: 55.5%, $space: hsl) !default;
@@ -171,7 +171,7 @@ $chat-file-secondary-color: null !default;
   $chat-typingindicator-circle-bg-color-center: color.adjust($base-bg, $lightness: 43.92%, $space: hsl) !default;
 
   $chat-file-container-box-shadow: 0 0 2px 0 color.change($base-shadow-color, $alpha: 0.28), 0 1px 2px 0 color.change($base-shadow-color, $alpha: 0.32) !default;
-  $chat-file-secondary-color: darken($base-text-color, 40.00) !default;
+  $chat-file-secondary-color: color.adjust($base-text-color, $lightness: -40.00%, $space: hsl) !default;
 }
 
 /**