chore: use export as syntax (#243)

Author: technote-space

src/index.ts

@@ -2,7 +2,7 @@ import Logger from './logger';
 import Command from './command';
 import ApiHelper from './api-helper';
 import GitHelper from './git-helper';
-import * as Utils from './utils';
-import * as ContextHelper from './context-helper';
+export * as Utils from './utils';
+export * as ContextHelper from './context-helper';
 
-export { Logger, Command, ApiHelper, GitHelper, Utils, ContextHelper };
+export { Logger, Command, ApiHelper, GitHelper };