feature: Add additional operator webhook configuration fields

[solidDoWant]

Chart name and version, where you feel a lack of requested feature
chart: victoria-metrics-operator
version: v0.42.1

Is your feature request related to a problem? Please describe.
I'm pretty picky with my PKI/certificate setup. I like all my certs having a subject with specific information in it, and I like short-lived (duration measured in hours instead of years) certificates.

As the operator chart stands today, it is missing a couple of things that make this somewhat difficult to do:

• There is no option to set the subject field on the created admission webhook certificate.
• There is no option to set labels on different chart components, such as the webhook cert secret. Labels are often used with short-lived secrets, in combination with external automation tools, to restart deployments when certificates are re-issued.

Describe the solution you'd like
I would like for the Helm values file to pass subject parameters to the certificate manifest. I would also like the ability to pass labels and annotations to the created certificate-created secret (this can done via the secretTemplate field).

Describe alternatives you've considered
These can be set via external tools that manage Helm, such as FluxCD. This is a little more brittle than setting the values via the actual chart though.

Additional context
I think that this would be a pretty small change and would be willing to file a PR for it, if feature is acceptable.