Feat: add feature flag for dynamically setting ServiceAccount Role ARN annotation

[korenyoni]

what

• Add feature flag for dynamically setting ServiceAccount Role ARN annotation, which is set to true by default.
• Misc: change wording for var.service_account_namespace to avoid confusion between var.namespace and var.kubernetes_namespace.

why

• Assuming the Helm Chart follows the standard convention of rendering ServiceAccount annotations in serviceAccount.annotations, this allows the ServiceAccount created by the Helm Chart to assume the IAM Role in question via the EKS OIDC IdP, without the consumer of this module having to set this annotation via var.values or var.set, which would involve manually rendering the IAM Role ARN beforehand (since not doing so would introduce a cycle in the graph).

references

• N/A