Requests to Slack exceeded the rate limit

[Matt2298]

Description:
When trying to create a group of sentry_issue_alerts resources, we're hitting an error whereby Slack is rate limiting the number of calls we can make to it's API. As a result, any apply jobs that run and create quite a few alerts will fail, also corrupting the terraform state.

Example
We have ~281 alerts to be created, most of which look very similar to the following definition:

resource "sentry_issue_alert" "alert_rule" {
  for_each     = var.alert_rules
  organization = var.organisation
  project      = sentry_project.project.id
  name         = each.key
  environment  = each.value.environment
  frequency    = each.value.frequency
  actions      = each.value.actions
  conditions   = each.value.conditions
  filters      = each.value.filters
  action_match = "any"
  filter_match = "all"
}

An example alert rule:

"Sentry to Slack - channel - event seen - every 30 minutes" = {
      frequency   = 30
      environment = null
      actions = [{
        id        = "sentry.integrations.slack.notify_action.SlackNotifyServiceAction",
        channel   = "#sentry-my-team",
        workspace = local.my_team_workspace_id,
        tags      = "environment,level,user"
      }]
      conditions = [{
        id = "sentry.rules.conditions.first_seen_event.FirstSeenEventCondition"
      }]
      filters = [local.filter_not_devops]
    },
  })

It would be good if the terraform provider had some way of understanding this rate limit and backing off when errors start to occur. As a result of applying the above terraform, we recieve the following error:

│ Error: PUT https://app.getsentry.com/api/0/projects/my-project/my-app/rules/1234567/: 400 map[actions:[Slack: Requests to Slack exceeded the rate limit. Please try again later.]]
│ 
│   with module.my_app.sentry_issue_alert.alert_rule["Sentry to Slack - channel - event seen - every 30 minutes"],
│   on ../module/main.tf line 29, in resource "sentry_issue_alert" "alert_rule":
│   29: resource "sentry_issue_alert" "alert_rule" {

[hakubo]

There is this PR waiting for being fixed/approved: #282

[hakubo]

also this is a duplicate: #281

[jianyuan]

You can now set the input_channel_id parameter in v0.12.0!