Fix check on subclass for typing.Union in _infer_multiple_outputs for Python 3.10+

[Taragolis]

#36652 introduced bug for Python 3.10+ when task decorated function has annotation as object and not as class

This also fix broken main for Python 3.10+ tests:

• tests/always/test_example_dags.py::test_should_be_importable[tests/system/providers/google/cloud/cloud_sql/example_cloud_sql_query_postgres.py]
• tests/always/test_example_dags.py::test_should_be_importable[tests/system/providers/google/cloud/cloud_sql/example_cloud_sql_query_mysql.py]

airflow/tests/system/providers/google/cloud/cloud_sql/example_cloud_sql_query_postgres.py

Lines 197 to 198 in 59b32dc

	@task
	def get_public_ip() -> str | None:

Traceback (most recent call last):
  File "/Users/taragolis/Projects/common/airflow/tests/system/providers/google/cloud/cloud_sql/example_cloud_sql_query_postgres.py", line 198, in <module>
    def get_public_ip() -> str | None:
  File "/Users/taragolis/Projects/common/airflow/airflow/decorators/python.py", line 75, in python_task
    return task_decorator_factory(
  File "/Users/taragolis/Projects/common/airflow/airflow/decorators/base.py", line 646, in task_decorator_factory
    decorator = _TaskDecorator(
  File "<attrs generated init airflow.decorators.base._TaskDecorator>", line 8, in __init__
    _setattr('multiple_outputs', __attr_factory_multiple_outputs(self))
  File "/Users/taragolis/Projects/common/airflow/airflow/decorators/base.py", line 353, in _infer_multiple_outputs
    return issubclass(ttype, Mapping)
  File "/Users/taragolis/.pyenv/versions/3.10.1/lib/python3.10/typing.py", line 1138, in __subclasscheck__
    return issubclass(cls, self.__origin__)
  File "/Users/taragolis/.pyenv/versions/3.10.1/lib/python3.10/abc.py", line 123, in __subclasscheck__
    return _abc_subclasscheck(cls, subclass)
TypeError: issubclass() arg 1 must be a class

---

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[Taragolis]

During fix one problem another happen 🙄 🙄 🙄

FAILED tests/models/test_mappedoperator.py::test_mapped_render_template_fields_validating_operator - TypeError: Can't compile non template nodes
FAILED tests/models/test_mappedoperator.py::test_mapped_expand_kwargs_render_template_fields_validating_operator - TypeError: Can't compile non template nodes

However this fixes or othe merged PR should not be a reason for that, and it happen (I guess) only with never version of Jinja2==3.1.3 which are released for about 7 hours ago

< Jinja2==3.1.2
---
> Jinja2==3.1.3

[Taragolis]

Everything looks green except one non-relevant failure. Merge