Add support for mixed TLS and non-TLS endpoints in Query

[aeroyorch]

In multicluster deployments, internal sidecars are sometimes accessed over plain HTTP within the cluster, while external sidecars are exposed through ingresses that require TLS.

Is there currently a way to represent this mixed scenario (TLS + non-TLS endpoints) in the endpoint.sd-config file?. E.g.:

endpoints:
  - address: "store-internal-1:10901"

  - address: "store-external.example.com:443"
    grpc_client_config:
      tls_config:
        enabled: true
        insecure_skip_verify: false
        cert_file: ""
        key_file: ""
        ca_file: ""
      server_name: ""
      compression: "none"

From what I saw, it seems that all endpoints inherit the global gRPC TLS configuration.