vendor: Ignore github.com/hashicorp/terraform/backend
vendor: Ignore github.com/hashicorp/terraform/backend

This is to avoid dependency sprawl - e.g. vendoring AWS or Azure SDK
when we don't really need remote backend functionality
in provider code - it's core's responsibility.

haxorof/terraform-provider-openstack,haxorof/terraform-provider-openstack,haxorof/terraform-provider-openstack