修正一处拼写错误。

src/material-2-scheme.ts

@@ -28,7 +28,7 @@ export type MaterialDesign2SchemeSource = {
   custom_colors: Record<string, string>;
 };
 
-export type Materialdesign2SchemeStorage = {
+export type MaterialDesign2SchemeStorage = {
   source: MaterialDesign2SchemeSource;
   scheme: MaterialDesign2Scheme;
 };