Update pytest requirement from ~=7.2.2 to ~=7.3.1 (#142)

Updates the requirements on [pytest](https://github.com/pytest-dev/pytest) to permit the latest version.
- [Release notes](https://github.com/pytest-dev/pytest/releases)
- [Changelog](https://github.com/pytest-dev/pytest/blob/main/CHANGELOG.rst)
- [Commits](pytest-dev/pytest@7.2.2...7.3.1)

---
updated-dependencies:
- dependency-name: pytest
  dependency-type: direct:development
...

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

Author: dependabot[bot]

requirements-dev.txt

@@ -9,4 +9,4 @@
 # setup.py.
 coverage ~=7.1
 flake8 ~=5.0.4
-pytest ~=7.2.2
+pytest ~=7.3.1