`NoTelemetry` flag doesn't stop telemetry

[noot]

Describe the bug

• the --no-telemetry flag doesn't stop telemetry
• the only place the NoTelemetry flag is checked is dot/node.go

	if cfg.Global.NoTelemetry {
		return node, nil
	}

this prevents telemetry.GetInstance() from being called in dot/node.go. however in packages that use telemetry, NoTelemetry is not persisted and they end up calling telemetry.GetInstance() thus creating the telemetry instance, for example dot/network/service.go publishNetworkTelemetry.

Possible Solution

• I would recommend adding the NoTelemetry option to the telemetry package and creating a Instance interface that includes the functions the current *telemetry.Handler has. If NoTelemetry == true, then a *NoopHandler, which does nothing, can be created when GetInstance() is called. otherwise, the usual *Handler can be used.

To Reproduce