Do not expose internal type

Author: davidparsson

src/index.ts

@@ -5,4 +5,3 @@ export default new Factory().newBuilder();
 export type { JUnitReportBuilder as Builder } from './builder';
 export type { TestCase } from './test_case';
 export type { TestSuite } from './test_suite';
-export type { TestSuites } from './test_suites';