Apache环境下：PHP7.1以上后台打不开，前台正常；PHP7.0及以下都正常。

显示如下：

Internal Server Error

The server encountered an internal error or misconfiguration and was unable to complete your request.

Please contact the server administrator at admin@php.cn to inform them of the time this error occurred, and the actions you performed just before this error.

More information about this error may be available in the server error log.