MAINT: Bump hypothesis from 6.17.3 to 6.18.0

Bumps [hypothesis](https://github.com/HypothesisWorks/hypothesis) from 6.17.3 to 6.18.0.
- [Release notes](https://github.com/HypothesisWorks/hypothesis/releases)
- [Commits](HypothesisWorks/hypothesis@hypothesis-python-6.17.3...hypothesis-python-6.18.0)

---
updated-dependencies:
- dependency-name: hypothesis
  dependency-type: direct:production
  update-type: version-update:semver-minor
...

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

Author: dependabot[bot]

test_requirements.txt

@@ -1,7 +1,7 @@
 cython==0.29.24
 wheel<0.37.1
 setuptools<49.2.0
-hypothesis==6.17.3
+hypothesis==6.18.0
 pytest==6.2.5
 pytz==2021.1
 pytest-cov==2.12.1