Fixed typo (#124)

hg-pyun · Hyunje Jun · commit f039d0807360 · 2019-03-12T23:27:45.000+09:00
maybe messages
diff --git a/lib/types.ts b/lib/types.ts
@@ -547,7 +547,7 @@ export type ImageMapMessage = MessageCommon & {
   altText: string;
   baseSize: Size;
   /**
-   * Video to play inside a image map messagea
+   * Video to play inside a image map messages
    */
   video?: {
     /**
