add annotation linting

[charlesfrye]

command:

python -m flake8 --select=ANN --ignore=ANN101,ANN102,ANN002,ANN003,ANN202 \
--mypy-init-return --suppress-none-returning ./text-recognizer ./training

currently 228 lints

[charlesfrye]

copied from https://github.com/full-stack-deep-learning/fsdl-text-recognizer-2021/issues/74, the process for adding a new linting tool

because this uses flake8 and it's already installed in dev-lint, we just need to change the configuration to get it to lint in pre-commit and to run locally

Process:

• [ ] add to pre-commit
• [ ] lint all files
• [x] add to dev-lint environment
• [ ] run locally
• [x] add to tasks/lint.sh