Description of the problem, including code/CLI snippet

When running tox -e cli_func_v4 and you have a ~/.python-gitlab.cfg file as shown below, the tests will fail.

This is one of the causes of the test failures on #2702

[global]
ssl_verify = true
timeout = 60
per_page = 100

[dev]
url = https://dev.example.com
private_token = abcdefghijklmnop
api_version = 4

[prod]
url = https://prod.example.com
private_token = abcdefghijklmnop
api_version = 4

Expected Behavior

Tests should be independent of the testing user's home directory.

Actual Behavior

Tests fail if you choose to not have a default GitLab instance defined.

Specifications

• python-gitlab version: Current main branch: bf68485
• API version you are using (v3/v4): N/A
• Gitlab server version (or gitlab.com): 15.4.0-ee.0 (specified in tests/functional/fixtures/.env