Fix Static ALB healthcheck
Fix Static ALB healthcheck

The Application Load Balancer health check uses
this path for static's healthcheck.

This path has been removed so we can replace it
with its replacement in the corresponding PR:
https://github.com/alphagov/static/pull/2412

alphagov/govuk-puppet,alphagov/govuk-puppet,alphagov/govuk-puppet,alphagov/govuk-puppet,alphagov/govuk-puppet,alphagov/govuk-puppet