Backport of Fix logic on apigateway that ignores current annotations on services into release/1.2.x

[hc-github-team-consul-core]

Backport

This PR is auto-generated from #3597 to be assessed for backporting due to the inclusion of the label backport/1.2.x.

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The person who merged in the original PR is:
@missylbytes
This person should manually cherry-pick the original PR into a new backport PR,
and close this one when the manual backport PR is merged in.

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The below text is copied from the body of the original PR.

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Changes proposed in this PR

• Fixes for NET-7113
• Previously, any extra annotations added to a service controlled by an API Gateway would infinitely reconcile, as the Gateway would keep removing the extra annotations.
• Logic was added to prevent this, as well as prevent the same issue with labels.

How I've tested this PR

Built a local image and installed onto a Kind cluster with the following values:

# values.yaml
global:
  name: consul
  imageK8S: consul-k8s-control-plane:local

connectInject:
  enabled: true
  apiGateway:
    managedGatewayClass:
      copyAnnotations:
        service:
          annotations: |
            - cupcake

Then I created an API Gateway with the following values:

# gateway.yaml
apiVersion: gateway.networking.k8s.io/v1beta1
kind: Gateway
metadata:
  name: my-gateway
  annotations:
    cupcake: strawberry
spec:
  gatewayClassName: consul
  listeners:
  - protocol: HTTP
    port: 80
    name: http
    allowedRoutes:
      namespaces:
        from: "All"

These resulted in a service that looked like this:

---------- Testing Annotations -------------------------------------------------------------------------------------

I then edited the service to add an additional annotation

And after editing, I made sure this additional annotation was still there:

---------- Testing Labels -------------------------------------------------------------------------------------

I also tested for labels by editing the service and adding a label

Then looked at the service again to make sure the label stayed

How I expect reviewers to test this PR

Check out the tests, test manually

Checklist

• Tests added
• CHANGELOG entry added

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Overview of commits

• 4254967 - 3d9880a - d21117c - f17369b - ce75a10 - a0d0a44 - 2fb650e - 6e7d867 - 15f0144 - 768ea38