add http_headers config / disable provenance

[geekflyer]

Hi, thanks for this great provider! I'd like to disable provenance by setting the x-disable-provenance http header (https://github.com/grafana/terraform-provider-grafana/issues/845), however it appears you removed the http_headers setting from the provider settings due to some python binding issues https://github.com/lbrlabs/pulumi-grafana/issues/27 . Is there a chance we could add the http_headers back? Or maybe simply expose a disableProvenance setting that under the hood sets these headers. Thoughts?

[sionescu]

Any news on this ? @tenwit @usrbinkat @ringods