Rails Health Controller monkey patch

[oz-tal]

I'd like to suggest this change to address this issue: https://github.com/interdiscipline/lockup/issues/77

Override the lockup check method to do nothing in the Rails health controller.

According to my test, using skip_before_action trigger the rescue_from(Exception) defined here, even with the raise: false option. For this reason, overriding the check seem appropriate instead.

This simple monkey-patch should gracefully do nothing on older version of Rails where the Rails::HealthController doesn't exist.