Add a mutating webhook

[nwmcsween]

What would you like to be added?

Similar to bank-vaults, etc create a mutating webhook to modify Kubernetes resources at runtime, the alternative is having a hard requirement on KRO style runtime chaining.

Why is this needed?

Allows netbox-operator to be used without having to rely on external projects.

[bruelea]

Thanks for creating this issue. Which resources would you like to be modified by the mutating webhook? Could it be implemented in a generic way, so that different resource kinds could be modified?