Add db-sync command to lando

Create a command that uses drush sql-sync to import a prod db to a local multisite installation.

*You must have the @remote.SITE and @local.SITE drush aliases set up.

tooling:
  db-sync:
    service: appserver
    cmd: site=${0} && drush sql-sync @remote.${site} @local.${site}

To use: lando db-sync SITE