Mailhog required for some commands

[danepowell]

My system information:

• BLT version: 8.5.2
• LAMP stack is DrupalVM 3.5.2

When I run this command:

blt local:refresh

I get the following output:

sh: 1: /opt/mailhog/mhsendmail: not found

@geerlingguy says "we should either choose mailhog in installed_extras by default, or switch the PHP mail command back to what it was"

I confirmed that adding mailhog to installed_extras fixes it.

[geerlingguy]

See #810 — this takes the former approach, and matches Drupal VM's default configuration. IMO this is better because having a mail catching utility running locally means no matter what, unless you explicitly override it, developers can't accidentally shoot out hundreds of emails to real email addresses :)