Basic Authentication support for Grafana Dashboard resources when using url

[tchelovilar]

Describe the solution you'd like

I would like to have HTTP authentication support for URL dashboards to have a private dashboard repository. Also would be nice to have the option to read the credentials from secrets.

Additional context It could be some extra options for the URL:

spec:
  urlAuthorization:
    basicAuth:
      username: username 
      passwordFrom:
        secretName: secret-name
        key: password