Merge pull request #1231 from VWS-Python/dependabot/pip/mypy-0.780

Bump mypy from 0.770 to 0.780

Author: adamtheturtle

dev-requirements.txt

@@ -16,7 +16,7 @@ flake8-quotes==3.2.0  # Require single quotes
 flake8==3.8.2  # Lint
 freezegun==0.3.15
 isort==4.3.21  # Lint imports
-mypy==0.770  # Type checking
+mypy==0.780  # Type checking
 pip-check-reqs-pip-gte-20==2.0.3.4
 pydocstyle==5.0.2  # Lint docstrings
 pyenchant==3.1.1  # Bindings for a spellchecking sytem