base/simplesaml needs mysql_root_password

Created by: slifty

When I run the simplesaml ansible script I get the following error:

    lever-for-change: fatal: [localhost]: FAILED! => {"msg": "The task includes an option with an undefined variable. The error was: 'mysql_root_password' is undefined\n\nThe error appears to be in '/data/www/torque-sites/base/simplesaml/ansible/roles/simplesaml/tasks/main.yml': line 20, column 3, but may\nbe elsewhere in the file depending on the exact syntax problem.\n\nThe offending line appears to be:\n\n\n- name: Create database user\n  ^ here\n"}

None of the group_vars for the various environments have a mysql_root_password so I'm wondering if that should be added, or if there's some other place I should be setting mysql_root_password.