Update xarray/core/dataarray.py

Author: max-sixty

xarray/core/dataarray.py

@@ -6708,6 +6708,7 @@ def interp_calendar(
     def groupby(
         self,
         group: GroupInput = None,
+        *,
         squeeze: Literal[False] = False,
         restore_coord_dims: bool = False,
         **groupers: Grouper,