Fix groupby failures in dask_cudf CI (#11561)

Dask-cudf groupby tests *should* be failing as a result of dask/dask#9302 (see [failures](https://gpuci.gpuopenanalytics.com/job/rapidsai/job/gpuci/job/cudf/job/prb/job/cudf-gpu-test/CUDA=11.5,GPU_LABEL=driver-495,LINUX_VER=ubuntu20.04,PYTHON=3.9/9946/) in #11565 is merged - where dask/main is being installed correctly).  This PR updates the dask_cudf groupby code to fix these failures.

Authors:
  - Richard (Rick) Zamora (https://github.com/rjzamora)

Approvers:
  - GALI PREM SAGAR (https://github.com/galipremsagar)

URL: #11561

python/dask_cudf/dask_cudf/groupby.py

@@ -249,7 +249,7 @@ def last(self, split_every=None, split_out=1):
         )
 
     @_dask_cudf_nvtx_annotate
-    def aggregate(self, arg, split_every=None, split_out=1):
+    def aggregate(self, arg, split_every=None, split_out=1, shuffle=None):
         if arg == "size":
             return self.size()
 
@@ -274,7 +274,12 @@ def aggregate(self, arg, split_every=None, split_out=1):
             )
 
         return super().aggregate(
-            arg, split_every=split_every, split_out=split_out
+            arg,
+            split_every=split_every,
+            split_out=split_out,
+            # TODO: Change following line to `shuffle=shuffle,`
+            # when dask_cudf is pinned to dask>2022.8.0
+            **({} if shuffle is None else {"shuffle": shuffle}),
         )
 
 
@@ -436,7 +441,7 @@ def last(self, split_every=None, split_out=1):
         )[self._slice]
 
     @_dask_cudf_nvtx_annotate
-    def aggregate(self, arg, split_every=None, split_out=1):
+    def aggregate(self, arg, split_every=None, split_out=1, shuffle=None):
         if arg == "size":
             return self.size()
 
@@ -459,7 +464,12 @@ def aggregate(self, arg, split_every=None, split_out=1):
             )[self._slice]
 
         return super().aggregate(
-            arg, split_every=split_every, split_out=split_out
+            arg,
+            split_every=split_every,
+            split_out=split_out,
+            # TODO: Change following line to `shuffle=shuffle,`
+            # when dask_cudf is pinned to dask>2022.8.0
+            **({} if shuffle is None else {"shuffle": shuffle}),
         )
 
 

python/dask_cudf/dask_cudf/tests/test_groupby.py

@@ -575,12 +575,12 @@ def test_groupby_categorical_key():
     ddf = gddf.to_dask_dataframe()
 
     got = (
-        gddf.groupby("name")
+        gddf.groupby("name", sort=True)
         .agg({"x": ["mean", "max"], "y": ["mean", "count"]})
         .compute()
     )
     expect = (
-        ddf.groupby("name")
+        ddf.groupby("name", sort=True)
         .agg({"x": ["mean", "max"], "y": ["mean", "count"]})
         .compute()
     )