host-containers: render config file with if_not_null

[sam-berning]

Issue number:

N/A

Description of changes:

#3777 would skip rendering enabled or superpowered when they were set to false because the if handlebars helper checks for any falsy value. This instead checks that settings values are not null with the new if_not_null helper before rendering them, allowing false values to be rendered correctly.

Testing done:

Spun up an aws-dev instance and modified settings, verifying that the config file was updated correctly.

Terms of contribution:

By submitting this pull request, I agree that this contribution is dual-licensed under the terms of both the Apache License, version 2.0, and the MIT license.