Show which user was queried when users_not_found returned by data source

[edify42]

Hi @pablovarela !

We use the datasource like below for a number of users who signin via SSO and we maintain a list of them with terraform that can do other things like below:

data "slack_user" "by_email" {
  for_each = toset(flatten([
    [var.users_in_teams["team_x"]],
    [var.users_in_teams["team_y"]],
    [var.users_in_teams["team_z"]],
    [var.users_in_teams["team_a"]],
    [var.users_in_teams["team_b"]]
  ]))
  email = each.key
}

Sometimes people leave our org and their email is no longer valid in slack. The provider currently returns the below:

Error: users_not_found

  on users-slack-info.tf line 1, in data "slack_user" "by_email":
   1: data "slack_user" "by_email" {

Without the detail into which user left. making it hard for us to figure it out quickly. I can make a PR to output which user it was that left (either their name or email)

[pablovarela]

Implemented by #70

[edify42]

Thanks mate ❤️

Error: not found [email protected]: users_not_found

  on users-slack-info.tf line 1, in data "slack_user" "by_email":
   1: data "slack_user" "by_email" {