Added metavar and choices to --state flag in airflow dags list-jobs CLI for suggesting valid state arguments.

airflow/cli/cli_config.py

@@ -37,6 +37,7 @@
 from airflow.settings import _ENABLE_AIP_44
 from airflow.utils.cli import ColorMode
 from airflow.utils.module_loading import import_string
+from airflow.utils.state import DagRunState
 from airflow.utils.timezone import parse as parsedate
 
 BUILD_DOCS = "BUILDING_AIRFLOW_DOCS" in os.environ
@@ -277,7 +278,13 @@ def string_lower_type(val):
 ARG_NO_BACKFILL = Arg(
     ("--no-backfill",), help="filter all the backfill dagruns given the dag id", action="store_true"
 )
-ARG_STATE = Arg(("--state",), help="Only list the dag runs corresponding to the state")
+dagrun_states = tuple(state.value for state in DagRunState)
+ARG_STATE = Arg(
+    ("--state",),
+    help="Only list the dag runs corresponding to the state",
+    metavar=", ".join(dagrun_states),
+    choices=dagrun_states,
+)
 
 # list_jobs
 ARG_DAG_ID_OPT = Arg(("-d", "--dag-id"), help="The id of the dag")