Add streaming key to the requests

[itsmylife]

What is this?

In this PR each request has a unique streaming key with orgId to identify the organizations. So different organizations will have separate streams. On the frontend we generate and send that key and on the backend we use it to store the topic and use orgID provided. If the orgID is different than the plugin configuration this will return an error and subscribing to the stream will be failed.

The idea was taken from

• https://github.com/grafana/falconlogscale-datasource/blob/02a48c3224b139423a190583939a80cb80b8b7da/src/streaming.ts#L9
• https://github.com/grafana/falconlogscale-datasource/blob/02a48c3224b139423a190583939a80cb80b8b7da/pkg/plugin/streaming.go#L17-L62

How to test?

• In mqtt repository
  • Run mage -v
  • Run yarn dev
  • Run yarn broker
• In grafana repository
  • Run grafana as usual
• Create an mqtt datasource
• Run query for millisecond/1000 and see in developer tools it's sending a streaming key with orgID.