Auto detect `is_bad_events` of `newrelic_service_level_alert_helper`

[sato-s]

Feature Description

Currently, we need to specify a is_bad_events of newrelic_service_level_alert_helper based on the SLI definition.
This is bit cumbersome when we have imported SLI(defined with UI).

I think we can detect this property by querying a sli_guid.
How about letting newrelic_service_level_alert_helper detect is_bad_events automatically if is_bad_events is null?

Describe Alternatives

The data source like newrelic_service_level with is_bad_events property would also solve the problem.