【Laravel】herokuデプロイエラー

前提・実現したいこと

laravelで開発したサービスをherokuにデプロイ中に、git push heroku master でエラーが発生してしまいます。

発生している問題・エラーメッセージ

（省略）
remote: In AppServiceProvider.php line 30:
remote:
remote:syntax error, unexpected end of file, expecting function (T_FUNCTION) or co
remote:nst (T_CONST)
emote:
remote:
remote:        Script @php artisan package:discover --ansi handling the post-autoload-dump event returned with error code 1
remote:  !     WARNING: A post-autoload-dump script terminated with an error
remote:
remote:  !     ERROR: Dependency installation failed!
remote:  !
remote:  !     The 'composer install' process failed with an error. The cause
remote:  !     may be the download or installation of packages, or a pre- or
remote:  !     post-install hook (e.g. a 'post-install-cmd' item in 'scripts')
remote:  !     in your 'composer.json'.
remote:  !
remote:  !     Typical error cases are out-of-date or missing parts of code,
remote:  !     timeouts when making external connections, or memory limits.
remote:  !
remote:  !     Check the above error output closely to determine the cause of
remote:  !     the problem, ensure the code you're pushing is functioning
remote:  !     properly, and that all local changes are committed correctly.
remote:  !
remote:  !     For more information on builds for PHP on Heroku, refer to
remote:  !     https://devcenter.heroku.com/articles/php-support
remote:  !
remote:  !     - Your 'composer.lock' is out of date!
remote:  !     - A post-autoload-dump script terminated with an error
remote:
（省略）