`CUstream` does not compare when the underlying pointer is the same

[leofang]

See CI failure: https://github.com/NVIDIA/cuda-python/actions/runs/13488648820/job/37683655417?pr=463#step:18:264

>       assert other_stream.handle == stream.handle
E       assert <CUstream 0x559c33ea2e20> == <CUstream 0x559c33ea2e20>
E        +  where <CUstream 0x559c33ea2e20> = <cuda.core.experimental._stream.Stream object at 0x7fd4dd21e1d0>.handle
E        +  and   <CUstream 0x559c33ea2e20> = <cuda.core.experimental._stream.Stream object at 0x7fd4de7b7f40>.handle

tests/test_stream.py:93: AssertionError