Limit the Deployment Health Query

What does this MR do and why?

• We're currently missing quite a few metrics for deployment health at the moment
• As we fix this, I'd like to ensure that we do not negatively impact our current usage of this query
• Until we validate that a target service that has been added is stable, let's ensure that we exclude that item from our query
• Note that this commit is effectively the same query utilized today, but we're doing the opposite
  • Doing so will allow us to add new services to the deployment health metric

Addresses: gitlab-com/gl-infra/delivery#2527 (closed)

Describe in detail what your merge request does and why.

Author Check-list

• Has documentation been updated?