fix: add content type parser for multipart/form-data

BREAKING CHANGE: no longer supports the content type `multipart`.

lib/main.js

@@ -243,7 +243,7 @@ const EikService = class EikService {
 				req.raw[_multipart] = true;
 				cb();
 			}
-			app.addContentTypeParser("multipart", setMultipart);
+			app.addContentTypeParser("multipart/form-data", setMultipart);
 
 			// Compression
 			await app.register(compression, {