Add python 3.11 build to GPU CI (#376)

* Add python 3.11 build to GPU CI

* Switch to `cupy-cuda11x`

Previously CuPy built a wheel for each CUDA `X.Y` version. However the
CuPy team later transitioned to CUDA Compatibility, which allows a wheel
build to only focus on CUDA major version. So switch to that wheel here.

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Co-authored-by: jakirkham <jakirkham@gmail.com>

Author: charlesbluca

continuous_integration/gpuci/axis.yaml

@@ -1,6 +1,7 @@
 PYTHON_VER:
 - "3.9"
 - "3.10"
+- "3.11"
 
 CUDA_VER:
 - "11.8.0"

continuous_integration/gpuci/build.sh

@@ -41,7 +41,7 @@ rapids-logger "Activate conda env"
 conda activate dask_image
 
 rapids-logger "Install cupy"
-python -m pip install cupy-cuda112 -f https://pip.cupy.dev/pre
+python -m pip install cupy-cuda11x -f https://pip.cupy.dev/pre
 
 rapids-logger "Install dask-image"
 python -m pip install .