Values:
STATE_UNSPECIFIED (0):
Default value. This value is unused.
CREATING (1):
Gateway is being created.
UPDATING (2):
Gateway is being updated.
DELETING (3):
Gateway is being deleted.
RUNNING (4):
Gateway is running.
DOWN (5):
Gateway is down and may be restored in the
future. This happens when CCFE sends
ProjectState = OFF.
ERROR (6):
ClientGateway encountered an error and is in
indeterministic state.