Addresses #15261.
Add tests.

PR Summary

In response to Issue #15261 and is a part of the NativeCommandArgumentPassing experimental feature.
The feature doesn't actually break --% as the argument list is created correctly when --% is present. However,
find.exe has some very specific behavior which is problematic when using the ArgumentList code path.

#15261 has more details.

PR Context

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• Breaking changes
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  • Experimental feature(s) needed
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  • Not Applicable
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  • Documentation needed
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  • N/A or can only be tested interactively
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