Internal validation of the provider failed

[antonbabenko]

To Reproduce

$ terraform version
Terraform v0.11.11
+ provider.dropbox (unversioned)

provider "dropbox" {}

data "dropbox_user_current" "curr" {}

output "user_id" {
  value = "${data.dropbox_user_current.curr.account_id}"
}

$ terraform plan

Error: provider.dropbox: Internal validation of the provider failed! This is always a bug
with the provider itself, and not a user issue. Please report this bug:

1 error occurred:
	* resource dropbox_folder_members: No Update defined, must set ForceNew on: []string{"message", "quiet"}

[callensm]

Fixed in PR #8