Expose EMF TCP and UDP ports, and others, in the service

[lucabrunox]

Description of changes:

Currently the operator creates a service for the agent with a fixed set of ports, without taking into account the agent configuration. That means adding emf: {} to the cwagent config will make the container listen to the ports 25888 tcp and udp, but the service does not add these ports.

The change does a little bit of refactoring to make the service ports the same as the container ports. I've split the commits to be more readable:

• First the getContainerPorts function is made self-contained and it's moved to the ports.go file. This is not changing functionality, it's just moving it around.
• Then change service.go to convert getContainerPorts into ServicePorts.
• Finally add support for both TCP and UDP ports for EMF.

Manual testing:

This is an example k8s service having the ports 25888 for EMF when using the new operator image:

amazon-cloudwatch   service/cloudwatch-agent                                  ClusterIP   10.100.72.71     <none>        4315/TCP,4316/TCP,2000/TCP,25888/TCP,25888/UDP   14d
amazon-cloudwatch   service/cloudwatch-agent-headless                         ClusterIP   None             <none>        4316/TCP,2000/TCP,25888/TCP,25888/UDP,4315/TCP   14d

And the CWA container ports:

Controlled By:  DaemonSet/cloudwatch-agent
Containers:
  otc-container:
    Container ID:   containerd://d2e40914eb4ec970eac4a1676bbffc72b6acdfd1cd64df9c89e89bf226b7914a
    Image:          public.ecr.aws/cloudwatch-agent/cloudwatch-agent:1.300039.0b612
    Image ID:       public.ecr.aws/cloudwatch-agent/cloudwatch-agent@sha256:4e5ecc0152c99b338f06044963f2d451e7f6f09ea61723b80be14e8749e1ca4e
    Ports:          4315/TCP, 4316/TCP, 2000/TCP, 25888/TCP, 25888/UDP

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[lisguo]

lgtm

[straussb]

Does the port Name need to correspond to anything else? Docs say "When considering the endpoints for a Service, this must match the 'name' field in the EndpointPort." Does that apply for us?

[straussb]

Spoke with @lisguo offline, we do not create Endpoints in the operator, so there's nothing to worry about here.