[BUG] VCS URLs are detected as path on linux systems

[jkowalleck]

issue

'git+https://github.com/path/to/package-one@41b95ec#egg=package-one'
is detected as a path, but actually it is just a VCS url

expected:

'git+https://github.com/path/to/package-one@41b95ec#egg=package-one'
is NOT detected as a path

reason:

def _looks_like_path(name: str) -> bool:
    """Checks whether the string ``name``  "looks like" a path on the filesystem.

    This does not check whether the target actually exists, only judge from the
    appearance.

    Returns true if any of the following conditions is true:
    * a path separator is found (either os.path.sep or os.path.altsep);
    * a dot is found (which represents the current directory).
    """
    if not name:
        return False
    if os.path.sep in name:
        return True
        # exists here, on linux/unix, as there is a '/' in the name
    # ...