Removes unused `database-vars.yml` file
Removes unused `database-vars.yml` file

All default variables for the `database` role are now stored in the role
defaults directory, consistent with Ansible best practices. Custom
variable overrides are still possible at the site level, including:

  * play-level vars (easiest)
  * group-level vars
  * host-vars
  * extra vars

Folks running these roles in other environments can use one of the above
strategies to customize the config.

freedomofpress/fingerprint-securedrop,freedomofpress/FingerprintSecureDrop,freedomofpress/FingerprintSecureDrop,freedomofpress/fingerprint-securedrop,freedomofpress/fingerprint-securedrop