Fix lint errors

apps/node-ts/ffmpeg/help.ts

@@ -1,7 +1,8 @@
+import type { FFmpegCoreModule } from "@ffmpeg/types";
 import createFFmpeg from "@ffmpeg/core";
 
 void (async () => {
-  const ffmpeg = await createFFmpeg();
+  const ffmpeg = (await createFFmpeg()) as FFmpegCoreModule;
   ffmpeg.setLogger(({ message }) => console.log(message));
   console.log("return code: ", ffmpeg.exec("-h"));
 })();