If the path represents an actual entry that is a symlink, returns the symlink’s absolute destination.

- Important: This is not exhaustive, the resulting path may still contain a symlink.
- Important: The path will only be different if the last path component is a symlink, any symlinks in prior components are not resolved.
- Note: If file exists but isn’t a symlink, returns `self`.
- Note: If symlink destination does not exist, is*not** an error.