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)

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

setup.py

@@ -12,7 +12,7 @@
 
 EXTRAS_REQUIRE = {
     "tests": ["pytest"],
-    "lint": ["flake8==3.9.0", "flake8-bugbear==20.11.1", "pre-commit~=2.7"],
+    "lint": ["flake8==3.9.0", "flake8-bugbear==21.4.3", "pre-commit~=2.7"],
 }
 EXTRAS_REQUIRE["dev"] = EXTRAS_REQUIRE["tests"] + EXTRAS_REQUIRE["lint"] + ["tox"]