fix: improve color contrast in AlertBox info variant

- Change info background from bg-info-600 to bg-info-400
- Improves text contrast ratio to meet WCAG 2.1 AA standards
- Ensures better readability for users with visual impairments

The darker background (info-400) provides better contrast with
white text, meeting the minimum 4.5:1 contrast ratio requirement.

Fixes #8290

Author: Ju-MINJAE

packages/ui-components/src/Common/AlertBox/index.module.css

@@ -47,7 +47,7 @@
   }
 
   &.info {
-    @apply bg-info-600;
+    @apply bg-info-400;
 
     .title {
       @apply bg-info-700;