Microsoft Windows has Universal Naming Convention (UNC) paths, see
<https://learn.microsoft.com/en-us/dotnet/standard/io/file-path-formats#unc-paths>
The Rust standard library normalizes paths to this form when calling
`std::fs::canonicalize`, see
<https://doc.rust-lang.org/std/fs/fn.canonicalize.html>
However, some programs, do not parse these paths correctly, including
our ally `git`:
$ git clone \\?\C:\Users\lorenz\tmp
Cloning into 'tmp'...
ssh: Could not resolve hostname \\\\?\\c: No such host is known.
fatal: Could not read from remote repository.
Please make sure you have the correct access rights
and the repository exists.
The `dunce` crate solves the problem of having to deal with
normalization and avoiding weird UNC paths for us. Note that on
non-Windows platforms, it *behaves exactly like*
`std::fs::canonicalize`!
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