pytest warning about pkg_resources being deprecated as an API

[Alexandru Zbarcea]

Warning about deprecation during pytest run:

==================================================== warnings summary ====================================================
.venv/lib/python3.10/site-packages/pkg_resources/__init__.py:121
  vdirsyncer/.venv/lib/python3.10/site-packages/pkg_resources/__init__.py:121: DeprecationWarning: pkg_resources is deprecated as an API
    warnings.warn("pkg_resources is deprecated as an API", DeprecationWarning)

.venv/lib/python3.10/site-packages/pkg_resources/__init__.py:2870
.venv/lib/python3.10/site-packages/pkg_resources/__init__.py:2870
.venv/lib/python3.10/site-packages/pkg_resources/__init__.py:2870
.venv/lib/python3.10/site-packages/pkg_resources/__init__.py:2870
  vdirsyncer/.venv/lib/python3.10/site-packages/pkg_resources/__init__.py:2870: DeprecationWarning: Deprecated call to `pkg_resources.declare_namespace('sphinxcontrib')`.
  Implementing implicit namespace packages (as specified in PEP 420) is preferred to `pkg_resources.declare_namespace`. See https://setuptools.pypa.io/en/latest/references/keywords.html#keyword-namespace-packages
    declare_namespace(pkg)

• Your vdirsyncer version: 0.19.1-079a156
• If applicable, which server software (and which version) you're using: NA
• Your Python version: 3.10.10
• Your operating system: archlinux
• Your config file:

[general]
status_path = "~/.vdirsyncer/status/"

[pair contacts]
a = "contacts_local"
b = "contacts_google"

collections = ["from a", "from b"]
metadata = ["color"]
conflict_resolution = "b wins"

[storage contacts_local]
type = "filesystem"
path = "~/.contacts/"
fileext = ".vcf"

[storage contacts_owncloud]
type = "carddav"
url = "https://owncloud.example.com/remote.php/carddav/"

[storage contacts_icloud]
type = "carddav"
url = "https://contacts.icloud.com/"

[storage contacts_google]
type = "google_calendar"
token_file = "~/.config/vdirsyncer/apps.googleusercontent.com.token"
client_id = "<id>"
client_secret = "<secret>"

[storage contacts_google_backup]
type = "singlefile"
path = "<path to google-contacts.vcf>"

• Use vdirsyncer -vdebug for debug output. The output is sensitive, but
  please attach at least the last few lines before the error (if applicable),
  censored as necessary. This is almost always the most useful information.

[Hugo]

Odd, the only usage of pkg_resources that I can see is in docs/conf.py. That's using when generating documentation, but not when running tests.

I wonder if this is a transitive dependency. It's not very helpful that the warning has no traceback.