make json default output option

grib_processor/main.py

@@ -121,7 +121,7 @@ def setup() -> tuple[Iterable[GribPayload], Callable[[GribPayload], None]]:
         "-o",
         "--output",
         choices=["amqp", "json"],
-        default="amqp",
+        default="json",
         help="Where to output processed grib messages to. Default is %(default)s.",
     )