Add trim to FileInfo (issue #70524)

[ichbinsteffen]

While debugging strange behavior I came across this issue today and had a few head scratching moments until I found that a
new FileInfo(path).Name returns a file name with a trailing space. I did not expect this behavior.

In a full file path, I think there is no risk in trimming it.
Of course it's a different story for directory paths.

I found this Issue (#70524) which I think fully captures this behavior and the discussion validates that it's a problem that deserves a fix.

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[stephentoub]

In a full file path, I think there is no risk in trimming it.

Spaces are valid characters in file names. The files "something.txt " and "something.txt" are not the same on all platforms.

[ichbinsteffen]

@stephentoub

Spaces are valid characters in file names. The files "something.txt " and "something.txt" are not the same on all platforms.

Ah, okay it's just that windows trims filenames. So unix systems always keep them, I didn't think of that.
Would platform specific behavior make sense?

[ichbinsteffen]

@dotnet-policy-service agree