Add tests for make_bat_command_line argument reconstruction

[StepfenShawn]

Resolves the FIXME in library/std/src/sys/args/windows.rs that noted tests were needed to ensure arguments are properly reconstructed by batch scripts.

[rustbot]

r? @Mark-Simulacrum

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[ChrisDenton]

This should ideally be running .bat scripts with the arguments and checking they pass through ok. Unit testing the function is only of limited use.

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[rustbot]

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