Turn on mypy check_untyped_defs = true

[Lee-W]

Description

mypy keeps warning us to use check_untyped_defs. When turning it on, I found out there're a few type annotation issues that could be improved and could potentially be an actual issue.

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Possible Solution

Fix the type annotation error/warning one by one

Additional context

list of modules needed to be fixed by 3.21.3

• commitizen/config/yaml_config.py
• commitizen/commands/init.py
• commitizen/config/toml_config.py
• commitizen/config/json_config.py
• commitizen/cz/base.py
• tests/test_factory.py
• commitizen/commands/changelog.py
• commitizen/commands/example.py
• commitizen/commands/commit.py
• commitizen/git.py
• tests/test_changelog.py
• commitizen/cli.py
• tests/test_cz_customize.py
• tests/test_cz_conventional_commits.py
• tests/test_cz_base.py
• commitizen/commands/info.py
• commitizen/commands/check.py

Additional context

No response