Python 3.9 mypy failures

[johnttompkins]

Following errors are thrown from MyPI when checking the support lib on python 3.9. To get this functional for 3.9 need to address:

mypy.....................................................................Failed
- hook id: mypy
- exit code: 2

src/cloudformation_cli_python_lib/interface.py:12: error: syntax error in type comment
src/cloudformation_cli_python_lib/interface.py:61: error: syntax error in type comment
src/cloudformation_cli_python_lib/interface.py:75: error: syntax error in type comment
src/cloudformation_cli_python_lib/interface.py:80: error: syntax error in type comment
src/cloudformation_cli_python_lib/interface.py:81: error: syntax error in type comment
src/cloudformation_cli_python_lib/interface.py:90: error: syntax error in type comment
src/cloudformation_cli_python_lib/interface.py:92: error: syntax error in type comment
src/cloudformation_cli_python_lib/interface.py:94: error: syntax error in type comment
src/cloudformation_cli_python_lib/interface.py:95: error: syntax error in type comment
src/cloudformation_cli_python_lib/interface.py:96: error: syntax error in type comment
src/cloudformation_cli_python_lib/interface.py:98: error: syntax error in type comment
src/cloudformation_cli_python_lib/interface.py:122: error: syntax error in type comment
src/cloudformation_cli_python_lib/interface.py:131: error: syntax error in type comment
src/cloudformation_cli_python_lib/interface.py:132: error: syntax error in type comment
src/cloudformation_cli_python_lib/interface.py:133: error: syntax error in type comment
src/cloudformation_cli_python_lib/interface.py:134: error: syntax error in type comment
src/cloudformation_cli_python_lib/interface.py:135: error: syntax error in type comment
src/cloudformation_cli_python_lib/interface.py:136: error: syntax error in type comment
src/cloudformation_cli_python_lib/interface.py:137: error: syntax error in type comment
src/cloudformation_cli_python_lib/interface.py:138: error: syntax error in type comment
src/cloudformation_cli_python_lib/interface.py:139: error: syntax error in type comment
src/cloudformation_cli_python_lib/interface.py:140: error: syntax error in type comment
src/cloudformation_cli_python_lib/interface.py:141: error: syntax error in type comment
src/cloudformation_cli_python_lib/interface.py:142: error: syntax error in type comment

[PatMyron]

maybe related to python/mypy#8614?
we need to update this at least:

cloudformation-cli-python-plugin/.pre-commit-config.yaml

Lines 51 to 52 in ae8533f

	- repo: https://github.com/pre-commit/mirrors-mypy
	rev: v0.711

[mmaeng]

#206 looks to resolve the mypy errors on Python 3.9 and 3.10