fix: add missing namespace to serviceaccount

[ohemelaar-dinum]

Description

This missing namespace prevents the operator from being deployed with argocd and helmfile in some cases. ServiceAccounts are a namespaced resource so it's best to always specify it.

Checklist

• No secrets, sensitive information, or unrelated changes
• Lint checks passing (make lint)
• Generated assets in-sync (make validate-generated-assets)
• Go mod artifacts in-sync (make validate-modules)
• Test cases are added for new code paths

Testing

[copy-pr-bot]

This pull request requires additional validation before any workflows can run on NVIDIA's runners.

Pull request vetters can view their responsibilities here.

Contributors can view more details about this message here.

[tariq1890]

Thanks for the contribution @ohemelaar-dinum ! Can you enable signoff in your commit to pass the DCO check?