Cannot setup new virtual environment

Hi,

This isn't really an issue with this package, but it's likely the first place people are going to go. I'm secretly hoping that there may be a simple change that can be implemented here to mitigate the issue.

The urllib3 migration appears to be in the process of being worked on in google-auth, but when setting up a new virtual environment, pip cannot resolve a version of urllib3 that allows this package to be installed, which breaks our ability to setup new virtual environments, use pre-commit, etc.

How to reproduce (tested on python 3.9.15):

cd /tmp
mkdir foo
cd foo
python -m virtualenv venv
. ./venv/bin/activate
pip install --index-url=https://pypi.org/pypi --isolated --upgrade pip  # I have the artifact registry in my pip.conf
pip install --index-url=https://pypi.org/pypi --isolated  keyrings.google-artifactregistry-auth

The above results in:

... <truncated for brevity> ...
    Collecting google-auth==2.19.1
      Using cached google_auth-2.19.1-py2.py3-none-any.whl (181 kB)
    Collecting keyring
      Using cached keyring-23.13.1-py3-none-any.whl (37 kB)
    Collecting keyrings.google-artifactregistry-auth
      Using cached keyrings.google_artifactregistry_auth-1.1.2-py3-none-any.whl (10 kB)
stderr:
    ERROR: Could not find a version that satisfies the requirement urllib3<2.0 (from google-auth) (from versions: 2.0.2)
    ERROR: No matching distribution found for urllib3<2.0

The resolved versions I know work today (resolved with pip-tools a few weeks ago):

#
# This file is autogenerated by pip-compile with Python 3.11
# by the following command:
#
#    make requirements[-dev,-lint,-gcpauth].txt
#

cachetools==5.3.0
    # via google-auth
certifi==2022.12.7
    # via requests
cffi==1.15.1
    # via cryptography
charset-normalizer==3.1.0
    # via requests
cryptography==40.0.1
    # via secretstorage
google-auth==2.17.1
    # via keyrings-google-artifactregistry-auth
idna==3.4
    # via requests
importlib-metadata==6.1.0
    # via keyring
jaraco-classes==3.2.3
    # via keyring
jeepney==0.8.0
    # via
    #   keyring
    #   secretstorage
keyring==23.13.1
    # via
    #   -r requirements-gcpauth.in
    #   keyrings-google-artifactregistry-auth
keyrings-google-artifactregistry-auth==1.1.2
    # via -r requirements-gcpauth.in
more-itertools==9.1.0
    # via jaraco-classes
pluggy==1.0.0
    # via keyrings-google-artifactregistry-auth
pyasn1==0.4.8
    # via
    #   pyasn1-modules
    #   rsa
pyasn1-modules==0.2.8
    # via google-auth
pycparser==2.21
    # via cffi
requests==2.28.2
    # via keyrings-google-artifactregistry-auth
rsa==4.9
    # via google-auth
secretstorage==3.3.3
    # via keyring
six==1.16.0
    # via google-auth
urllib3==1.26.15
    # via requests
zipp==3.15.0
    # via importlib-metadata

GoogleCloudPlatform / artifact-registry-python-tools

Cannot setup new virtual environment #45