Bump py from 1.9.0 to 1.10.0

Bumps [py](https://github.com/pytest-dev/py) from 1.9.0 to 1.10.0.
- [Release notes](https://github.com/pytest-dev/py/releases)
- [Changelog](https://github.com/pytest-dev/py/blob/master/CHANGELOG.rst)
- [Commits](pytest-dev/py@1.9.0...1.10.0)

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

Author: dependabot[bot]

requirements-dev.txt

@@ -1,6 +1,6 @@
 pytest==4.0.2
 attrs==19.1.0
-py==1.9.0
+py==1.10.0
 mock==3.0.5
 responses==0.3.0
 safety==1.8.7