fix typo

Author: robbtraister

src/index.js

@@ -290,7 +290,7 @@ class Offline {
     this.server = new Hapi.Server({
       connections: {
         router: {
-          stripTrailingSlash: !this.option.preserveTrailingSlash, // removes trailing slashes on incoming paths.
+          stripTrailingSlash: !this.options.preserveTrailingSlash, // removes trailing slashes on incoming paths.
         },
       },
     });