php-mcryptUbuntu Server 18.04 LTS 中是否缺少该软件包？
apt install php-mcrypt
Reading package lists... Done
Building dependency tree
Reading state information... Done
Package php-mcrypt is not available, but is referred to by another package.
This may mean that the package is missing, has been obsoleted, or
is only available from another source
E: Package 'php-mcrypt' has no installation candidate