machine run --file-local broken on windows

[erwin4928]

I'm unable to use this parameter on windows because it complains the guest path must be an absolute path yet it is.
I think it's evaluating the guest path as an absolute windows path when running the tool on windows. When I try an absolute windows path as the guest path I get different errors.

flyctl/internal/command/command_run.go

Line 309 in 44a8912

case !filepath.IsAbs(guestPath):