feat: allow service without authproxy

[afreyermuth98]

I want to be able to access the service without using the authproxy.
Moreover I added the way to put some custom labels and annotations on it

[CLAassistant]

All committers have signed the CLA.

[yorugac]

@afreyermuth98, thanks for the PR! We don't have an issue for this yet, so could you please describe more precisely the use cases you're facing?

FYI, there are rather large structural changes in manifests happening as part of #235, and authentication and metrics will be impacted as well. So this PR can be considered only after that work is done. Given the holidays, that'll probably be in the next year. Meanwhile, if you have the time to consider how your proposal will fit in into the new structure and updated manifests, I'd appreciate it greatly! (ref. PR: #512, also kubernetes-sigs/kubebuilder#3907)

[afreyermuth98]

Hello @yorugac ! Thanks for this answer :)
My needs are pretty simple :
I have an otel collector that is scraping my pods / service depending on their annotations and I do not (want to) set auth-proxy on my k6-operator setup. But the service is created only if auth-proxy is enabled so it blocks me.
With my PR, I can force to have a service (with custom annotations) to get it scraped and collect the metrics without having to set the auth-proxy.
Do not hesitate to reach me again if it's not clear / if something is needed :)