我部署到 heroku 是成功的，但是每当我尝试打开应用程序时它就会崩溃。我检查了 heroku 日志并收到以下错误：
fatal: Not a git repository (or any parent up to mount point /app)State changed from starting to crashed 2015-12-22T12:36:13.277955+00:00 heroku[web.1]: State changed from crashed to starting
2015-12-22T12:36:15.736462+00:00 heroku[web.1]: Starting process with command `bin/rails server -p 15638 -e production`
2015-12-22T12:36:18.003961+00:00 app[web.1]: fatal: Not a git repository (or any parent up to mount point /app)
2015-12-22T12:36:18.003980+00:00 app[web.1]: Stopping at filesystem boundary (GIT_DISCOVERY_ACROSS_FILESYSTEM not set).
2015-12-22T12:36:18.006461+00:00 app[web.1]: fatal: Not a git repository (or any parent up to mount …