Declare minimum Puppet version to be 6.24.0
Declare minimum Puppet version to be 6.24.0

In a565ea97609979f7ccbc407534a553def0e865d8 the commands are passed as
an array, but this feature was only introduced in Puppet 6.24.0[1]. This
raises the minimum version to match, since it's no longer possible to
use the module on anything older.

[1]: https://puppet.com/docs/puppet/6/release_notes_puppet.html#enhancements_puppet_x-7-9-0-PUP-5704

Fixes: a565ea97609979f7ccbc407534a553def0e865d8

puppetlabs/puppetlabs-apache,puppetlabs/puppetlabs-apache