feat: generate a k8s_name for test

[ImSingee]

Some extensions' name contain _, such as pg_ivm, pg_textsearch. Tests will fail on these extensions because this name violates k8s name's rule.

This PR fixes this by generating a k8s_name field in values.yaml and use this name as all k8s resource names.

[ImSingee]

Another thing I found when working on this PR: There's a e2e:test:all task available, but it executes e2e:test. However, the e2e:test task requires values.yaml file available for each target (which can be generated by e2e:generate-values). But currently there's no way to generate values file for all targets.

I think update e2e:test:all task's behaviour to execute e2e:test:all is better.

[NiccoloFei]

Hi @ImSingee , I think the preferred way here would be to go ahead with #9383 and lift this limitation on the extension Name field directly on the operator side.
The rule was originally created because K8S volume names need to comply with https://kubernetes.io/docs/concepts/overview/working-with-objects/names/#dns-label-names, and the extension's Name is being used to generate the related Volume name, but given that there are several extensions that want to use underscores I believe it would be better to sanitize the volume name in CNPG.

[ImSingee]

@NiccoloFei Yes, fixing it directly in cnpg will be better. But I think we can merge this PR first as that issue is just planned to resolve several months later. This is a test-only thing, we can easily revert this when the name with hypen is accpeted by cnpg. Also, merge this first can reduce unnecessary friction for other contributers.