Enable mypy strict mode (#8766)

Built on top of #8748, this PR reenables mypy strict mode and adds the appropriate corrections to pass the types checks.

* Upgrade mypy

* First step for acme

* Cast for the rescue

* Fixing types for certbot

* Fix typing for certbot-nginx

* Finalize type fixes, configure no optional strict check for mypy in tox

* Align requirements

* Isort

* Pylint

* Protocol for python 3.6

* Use Python 3.9 for mypy, make code compatible with Python 3.8<

* Pylint and mypy

* Pragma no cover

* Pythonic NotImplemented constant

* More type definitions

* Add comments

* Simplify typing logic

* Use vararg tuple

* Relax constraints on mypy

* Add more type

* Do not silence error if target is not defined

* Conditionally import Protocol for type checking only

* Clean up imports

* Add comments

* Align python version linting with mypy and coverage

* Just ignore types in an unused module

* Add comments

* Fix lint

* Work in progress

* Finish type control

* Isort

* Fix pylint

* Fix imports

* Fix cli subparser

* Some fixes

* Coverage

* Remove --no-strict-optional (obviously...)

* Update certbot-apache/certbot_apache/_internal/configurator.py

Co-authored-by: Brad Warren <bmw@users.noreply.github.com>

* Update certbot/certbot/_internal/display/completer.py

Co-authored-by: Brad Warren <bmw@users.noreply.github.com>

* Cleanup dns_google

* Improve lock controls and fix subparser

* Use the expected interfaces

* Fix code

Co-authored-by: Brad Warren <bmw@users.noreply.github.com>

certbot-dns-google/certbot_dns_google/_internal/dns_google.py

@@ -32,10 +32,6 @@ class Authenticator(dns_common.DNSAuthenticator):
                    'for DNS).')
     ttl = 60
 
-    def __init__(self, *args, **kwargs):
-        super(Authenticator, self).__init__(*args, **kwargs)
-        self.credentials = None
-
     @classmethod
     def add_parser_arguments(cls, add):  # pylint: disable=arguments-differ
         super(Authenticator, cls).add_parser_arguments(add, default_propagation_seconds=60)