lenient_issubclass does not work for generic aliases

[daviskirk]

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• I added a descriptive title to this issue
• I have searched (google, github) for similar issues and couldn't find anything
• I have read and followed the docs and still think this is a bug

Bug

Output of python -c "import pydantic.utils; print(pydantic.utils.version_info())":

             pydantic version: 1.7.3
            pydantic compiled: False
                 install path: /home/user/pydantic/pydantic
               python version: 3.9.0 (default, Nov 15 2020, 14:28:56)  [GCC 7.3.0]
                     platform: Linux-5.4.0-65-generic-x86_64-with-glibc2.31
     optional deps. installed: ['devtools', 'dotenv', 'email-validator', 'typing-extensions']

Using lenient_issubclass breaks for GernicAlias types.
This is important in python >= 3.9 as the typing become the default for defining types.

Reproducible example:

from pydantic.utils import lenient_issubclass
from collections.abc import Mapping
# should not raise an error here:
assert lenient_issubclass(list[str], Mapping) is False

raises:

    if lenient_issubclass(param.annotation, Request):
    \lib\site-packages\pydantic\utils.py:151: in lenient_issubclass
    return isinstance(cls, type) and issubclass(cls, class_or_tuple)
    \lib\abc.py:102: in __subclasscheck__
    return _abc_subclasscheck(cls, subclass)
E   TypeError: issubclass() arg 1 must be a class