Bump pytest from 4.0.2 to 4.1.0 in /flowclient

Bumps [pytest](https://github.com/pytest-dev/pytest) from 4.0.2 to 4.1.0.
- [Release notes](https://github.com/pytest-dev/pytest/releases)
- [Changelog](https://github.com/pytest-dev/pytest/blob/master/CHANGELOG.rst)
- [Commits](pytest-dev/pytest@4.0.2...4.1.0)

Signed-off-by: dependabot[bot] <support@dependabot.com>

Author: dependabot-support