Bump flake8-bugbear from 20.11.1 to 21.4.3

Bumps [flake8-bugbear](https://github.com/PyCQA/flake8-bugbear) from 20.11.1 to 21.4.3.
- [Release notes](https://github.com/PyCQA/flake8-bugbear/releases)
- [Commits](PyCQA/flake8-bugbear@20.11.1...21.4.3)

---
updated-dependencies:
- dependency-name: flake8-bugbear
  dependency-type: direct:development
  update-type: version-update:semver-major
...

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

Author: dependabot[bot]

poetry.lock

@@ -35,7 +35,7 @@ django = ">=2.0"
 black = "^21.6b0"
 flake8 = "^3.8.4"
 flake8-bandit = "^2.1.2"
-flake8-bugbear = "^20.11.1"
+flake8-bugbear = "^21.4.3"
 safety = "^1.10.3"
 pytest = "^6.2.1"
 mypy = "^0.902"