Add troubleshooting guide

[yorugac]

Feature Description

k6-operator now has new methods of installation which make it more accessible to broader public. But sometimes one needs to understand what has been deployed in order to fix it. Without lower-level knowledge, it can be time-consuming to resolve the issues. So adding a troubleshooting guide with common errors and gotcha's encountered during usage of k6-operator would be beneficial.

Suggested Solution (optional)

This guide should probably be part of OSS k6-docs but until we move there, it can be a separate doc here, in the repo.

Already existing or connected issues / PRs (optional)

No response

[immavalls]

Hi @yorugac based on https://community.grafana.com/t/k6-operator-logs-differ-from-running-locally/110547/3?u=eyeveebee and https://community.grafana.com/t/k6-operator-logs-differ-from-running-locally/110547/5 the guide might be a good place to add how to disable the quiet mode, so folks can get more information on what is going on when needed.

[yorugac]

@immavalls, I've tried to fit in quite option in troubleshooting guide but ended up adding a note about --verbose option in instead. The goal there is to troubleshoot k6-operator after all. While quiet is more about ~ troubleshooting k6 and the script. I think quite should be mentioned elsewhere, perhaps in #352

[yorugac]

Initial version of troubleshooting guide was added here:
https://github.com/grafana/k6-operator/blob/main/docs/troublehooting.md