[Doc] Improve description of metric field in databricks_job resource (#4595)

## Changes
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## Tests
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- [ ] `make test` run locally
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Co-authored-by: vuong-nguyen <[email protected]>

Author: alexott

NEXT_CHANGELOG.md

@@ -16,6 +16,7 @@
  * Improve documentation for `databricks_access_control_rule_set` ([#4580](https://github.com/databricks/terraform-provider-databricks/pull/4580)).
  * Correct `first_on_demand` documentation for `aws_attributes` in `databricks_cluster`.
  * Added file events permissions to GCP external location documentation. ([#4415](https://github.com/databricks/terraform-provider-databricks/pull/4415)).
+ * Improve description of `metric` field in `databricks_job` resource [#4595](https://github.com/databricks/terraform-provider-databricks/pull/4595)
 
 ### Exporter
 

docs/resources/job.md

@@ -468,7 +468,7 @@ The following parameter is only available on task level.
 This block describes health conditions for a given job or an individual task. It consists of the following attributes:
 
 * `rules` - (List) list of rules that are represented as objects with the following attributes:
-  * `metric` - (Required) string specifying the metric to check.  The only supported metric is `RUN_DURATION_SECONDS` (check [Jobs REST API documentation](https://docs.databricks.com/api/workspace/jobs/create) for the latest information).
+  * `metric` - (Required) string specifying the metric to check, like `RUN_DURATION_SECONDS`, `STREAMING_BACKLOG_FILES`, etc. - check the [Jobs REST API documentation](https://docs.databricks.com/api/workspace/jobs/create#health-rules-metric) for the full list of supported metrics.
   * `op` - (Required) string specifying the operation used to evaluate the given metric. The only supported operation is `GREATER_THAN`.
   * `value` - (Required) integer value used to compare to the given metric.