pkg_resources is deprecated as an API

[joaomcarlos]

Hi,

I am getting deprecation warnings:

.venv/lib/python3.11/site-packages/nameko_amqp_retry/backoff.py:2
 <proj> /.venv/lib/python3.11/site-packages/nameko_amqp_retry/backoff.py:2: DeprecationWarning: pkg_resources is deprecated as an API. See https://setuptools.pypa.io/en/latest/pkg_resources.html
    from pkg_resources import parse_version

.venv/lib/python3.11/site-packages/pkg_resources/__init__.py:3117
.venv/lib/python3.11/site-packages/pkg_resources/__init__.py:3117
  <proj>/.venv/lib/python3.11/site-packages/pkg_resources/__init__.py:3117: DeprecationWarning: Deprecated call to `pkg_resources.declare_namespace('zope')`.
  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)

-- Docs: https://docs.pytest.org/en/stable/how-to/capture-warnings.html

Seems like a pretty simple fix. The check probably doesnt even need to be there anymore to check the version of Kombu.

Thanks!