```release-note:enhancement
resource/aws_cloudwatch_metric_alarm: Add plan time validation to `alarm_name`, `comparison_operator`, `metric_name`, `metric_query.id`, `metric_query.expression`, `metric_query.metric.metric_name`, `metric_query.metric.namespace`, `metric_query.metric.unit`, `namespace`, `period`, `statistic`, `alarm_description`, `insufficient_data_actions`, `ok_actions`, `unit`, and `extended_statistic`
```