今天出现了以下异常：
Fetching gem metadata from https://gems.ruby-china.org/.
Retrying dependency api due to error (2/4): Bundler::HTTPError Net::HTTPInternalServerError: <h1>Internal Server Error</h1>
Retrying dependency api due to error (3/4): Bundler::HTTPError Net::HTTPInternalServerError: <h1>Internal Server Error</h1>
Retrying dependency api due to error (4/4): Bundler::HTTPError Net::HTTPInternalServerError: <h1>Internal Server Error</h1>
