Add hostAliases support for CrdbCluster pods

[eXist-FraGGer]

CrdbCluster did not expose a way to configure pod-level hostAliases, so users could not inject custom /etc/hosts entries for CockroachDB pods via the operator API..

Checklist

• adds spec.hostAliases to CrdbCluster API
• propagates hostAliases to StatefulSet pod template
• updates deepcopy for the new field
• extends CRD schemas in config/crd/bases and install/crds.yaml
• adds CSV spec descriptor for hostAliases
• updates example templates with hostAliases snippet
• adds StatefulSetBuilder golden test coverage for hostAliases

[cockroachlabs-cla-agent]

All committers have signed the CLA.

[eXist-FraGGer]

@udnay, @prafull11 Hello guys, let's review and discuss as it is very critical configuration.