Optional disable secret

[hoopty]

When using GitOps, we do not want secrets as part of the GitOps repo and should be able to be disable that secrets for use cases with rendered manifests. Please put a helm chart values override that can disable the population of the weaviate-cluster-api-basic-auth secret. If you want to provide an optional name override for the secret that is fine, but in my case I'll have my secrets operator create/maintain that secret prior to weaviate chart being deployed.