Add extraPorts to the server's Service resource

[HernanGatta]

Overview

This change allows one to specify additional ports in the Service resource created for the Vault pod(s).

The rationale is that, in our use case, we inject pods into certain kinds of workloads that in turn alter their traffic routing. As a result, the initial assumptions about networking no longer hold, and extra ports are necessary.

Based on a similar PR that added the same to the corresponding StatefulSet.

Testing

I added a new test and verified that my change works correctly, both via bats as well as on my own deployments.

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