fix(blazorui): resolve BitTheme js api issues in BlazorUI after adding target property to tsconfig #10219 (#10220)

Author: msynk

src/BlazorUI/Bit.BlazorUI/Utils/Theme/bit-theme.ts

@@ -89,3 +89,5 @@ class BitTheme {
 
     BitTheme.init(options);
 }());
+
+(window as any).BitTheme = BitTheme;