Add additional arguments to pass to the reduce function in map_reduce()

[bystepii]

This change allows additional arguments to be passed to the reduce function.

For example:

import lithops

args = [  # Init list of parameters for Lithops
    (1, 2),  # Args for function1
    (3, 4),  # Args for function2
    (5, 6),  # Args for function3
]  # End list of parameters for Lithops

def my_function(x, y, extra_param):
    print(f"Extra param: {extra_param}")
    return x + y

def my_reduce_function(results, extra_param):
    print(f"Extra param: {extra_param}")
    return sum(results)

if __name__ == "__main__":
    fexec = lithops.FunctionExecutor()
    fexec.map_reduce(my_function, args, my_reduce_function, extra_args=(1,), extra_args_reduce=(2,))
    print(fexec.get_result())

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[JosepSampe]

Cool! Thanks @bystepii