vectorize signature error message copy-paste issue

Description

Calling vectorize with a non-None value for the signature parameter outputs this error message about the excluded parameter.

NotImplementedError: cupy.vectorize does not support `excluded` option currently.

Inspecting the code, it is obvious there is a copy-paste error and the 2nd error message should be change excluded to signature.

https://github.com/cupy/cupy/blob/master/cupy/_functional/vectorize.py#L48-L54

        if excluded is not None:
            raise NotImplementedError(
                'cupy.vectorize does not support `excluded` option currently.')

        if signature is not None:
            raise NotImplementedError(
                'cupy.vectorize does not support `excluded` option currently.')

To Reproduce

# Write the code here
def foo(a,b):
    return a+b

np.vectorize(foo,signature="(m),(n)->()")

Installation

Conda-Forge (conda install ...)

Environment

N/A

Additional Information

No response

[rogerallen]

Not sure what the protocol is here, but this looks good to close, I think.

[tushxr16]

Hey @rogerallen ! Thanks for the help. I merged my first PR.