Refactor CategoricalSixColors to reduce color count

Updated the `CategoricalSixColors` property in the `ColorUtility` class to return an array of 6 unique colors instead of 12. Removed redundant instances of the color `#e8c600` for a cleaner and more concise representation.

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Author: gvreddy04

BlazorExpress.ChartJS/Utils/ColorUtility.cs

@@ -8,7 +8,7 @@ public static class ColorUtility
     /// Returns 6 categorical colors in the format #RRGGBB.
     /// <seealso href="https://spectrum.adobe.com/page/color-for-data-visualization/" />
     /// </summary>
-    public static string[] CategoricalSixColors => new[] { "#0fb5ae", "#4046ca", "#f68511", "#de3d82", "#7e84fa", "#72e06a", "#147af3", "#7326d3", "#e8c600", "#e8c600", "#e8c600", "#e8c600" };
+    public static string[] CategoricalSixColors => new[] { "#0fb5ae", "#4046ca", "#f68511", "#de3d82", "#7e84fa", "#72e06a" };
 
     /// <summary>
     /// Returns 12 categorical colors in the format #RRGGBB.