Bump pytest from 6.2.1 to 6.2.2 (AtsushiSakai#466)

Bumps [pytest](https://github.com/pytest-dev/pytest) from 6.2.1 to 6.2.2.
- [Release notes](https://github.com/pytest-dev/pytest/releases)
- [Changelog](https://github.com/pytest-dev/pytest/blob/master/CHANGELOG.rst)
- [Commits](pytest-dev/pytest@6.2.1...6.2.2)

Signed-off-by: dependabot[bot] <[email protected]>

Co-authored-by: dependabot[bot] <49699333+dependabot[bot]@users.noreply.github.com>

Author: dependabot[bot]

requirements.txt

@@ -3,4 +3,4 @@ scipy == 1.6.0
 pandas == 1.2.0
 matplotlib == 3.3.3
 cvxpy == 1.1.7
-pytest == 6.2.1
+pytest == 6.2.2