feat: support Python 3.14

[Linchin]

No description provided.

[Linchin]

There is still no samples test for python 3.14, nor 3.13

[Linchin]

Have added the 3.14 samples test, but still have unit tests to fix

[daniel-sanche]

why were these tests changed to async?

[parthea]

This change looks correct to me. My initial thought is that this should have been async based on this code

google-auth-library-python/google/auth/transport/_aiohttp_requests.py

Lines 122 to 153 in 9be6918

	class Request(transport.Request):
	"""Requests request adapter.
	This class is used internally for making requests using asyncio transports
	in a consistent way. If you use :class:`AuthorizedSession` you do not need
	to construct or use this class directly.
	This class can be useful if you want to manually refresh a
	:class:`~google.auth.credentials.Credentials` instance::
	import google.auth.transport.aiohttp_requests
	request = google.auth.transport.aiohttp_requests.Request()
	credentials.refresh(request)
	Args:
	session (aiohttp.ClientSession): An instance :class:`aiohttp.ClientSession` used
	to make HTTP requests. If not specified, a session will be created.
	.. automethod:: __call__
	"""
	def __init__(self, session=None):
	# TODO: Use auto_decompress property for aiohttp 3.7+
	if session is not None and session._auto_decompress:
	raise exceptions.InvalidOperation(
	"Client sessions with auto_decompress=True are not supported."
	)
	self.session = session
	async def __call__(

[vchudnov-g]

Sample tests for 3.14 are blocked on GoogleCloudPlatform/python-docs-samples#13596
Once that is merged, then we can submit internal cl/843750240.