Add in a missing library directive, missing new line (#370)

Author: kevmoo

.gitignore

@@ -4,4 +4,4 @@ pubspec.lock
 
 web_generator/lib/src/*.js
 web_generator/lib/src/*.js.*
-web_generator/lib/src/node_modules/
+web_generator/lib/src/node_modules/

web_generator/test/ts_bindings_test.dart

@@ -1,6 +1,6 @@
-// ignore_for_file: library_annotations
 @TestOn('vm')
 @Tags(['node'])
+library;
 
 import 'dart:io';