Version issue when installing on mac os

[petr-balogh]

Hello,

I am encountering the version issue when trying to install to the virtual env on mac os which block me to install from github master branch now.

When changing version in setup.cfg file to 0.9.1 it works ok, also when I remove the version.

(.venv) pbalogh@MacBook-Pro pytest_marker_bugzilla (ocs) $ pip install ./
Processing /Users/pbalogh/Code/OCS/pytest_marker_bugzilla
    Complete output from command python setup.py egg_info:
    ERROR:root:Error parsing
    Traceback (most recent call last):
      File "/Users/pbalogh/Code/OCS/pytest_marker_bugzilla/.venv/lib/python3.7/site-packages/pbr/core.py", line 96, in pbr
        attrs = util.cfg_to_args(path, dist.script_args)
      File "/Users/pbalogh/Code/OCS/pytest_marker_bugzilla/.venv/lib/python3.7/site-packages/pbr/util.py", line 270, in cfg_to_args
        pbr.hooks.setup_hook(config)
      File "/Users/pbalogh/Code/OCS/pytest_marker_bugzilla/.venv/lib/python3.7/site-packages/pbr/hooks/__init__.py", line 25, in setup_hook
        metadata_config.run()
      File "/Users/pbalogh/Code/OCS/pytest_marker_bugzilla/.venv/lib/python3.7/site-packages/pbr/hooks/base.py", line 27, in run
        self.hook()
      File "/Users/pbalogh/Code/OCS/pytest_marker_bugzilla/.venv/lib/python3.7/site-packages/pbr/hooks/metadata.py", line 26, in hook
        self.config['name'], self.config.get('version', None))
      File "/Users/pbalogh/Code/OCS/pytest_marker_bugzilla/.venv/lib/python3.7/site-packages/pbr/packaging.py", line 834, in get_version
        version = _get_version_from_git(pre_version)
      File "/Users/pbalogh/Code/OCS/pytest_marker_bugzilla/.venv/lib/python3.7/site-packages/pbr/packaging.py", line 774, in _get_version_from_git
        result = _get_version_from_git_target(git_dir, target_version)
      File "/Users/pbalogh/Code/OCS/pytest_marker_bugzilla/.venv/lib/python3.7/site-packages/pbr/packaging.py", line 736, in _get_version_from_git_target
        dict(new=new_version, target=target_version))
    ValueError: git history requires a target version of pbr.version.SemanticVersion(0.9.1), but target version is pbr.version.SemanticVersion(0.9.0)
    error in setup command: Error parsing /private/var/folders/_y/2zwzc3xj3y3139p_k4sz867c0000gn/T/pip-req-build-q9_qrtjo/setup.cfg: ValueError: git history requires a target version of pbr.version.SemanticVersion(0.9.1), but target version is pbr.version.SemanticVersion(0.9.0)