Restrict Python to 3.11.z in pyproject.toml

Pin Python to version 3.11 because the greenlet 2.0.2 module is not
building on Python 3.12.

For example, in Fedora 39 you have to install Python 3.11 with

sudo dnf install python3.11-devel

and select this version in poetry with

poetry env use python3.11

README.rst

@@ -16,7 +16,7 @@ A GPL-licensed Python library that facilitates functional testing of quipucords_
 Installation
 ^^^^^^^^^^^^
 
-Camayoc supports Python 3.11 and above. It uses `Poetry <https://python-poetry.org/>`_
+Camayoc supports Python 3.11. It uses `Poetry <https://python-poetry.org/>`_
 for dependency and virtual environment management. See Poetry documentation for
 installation instructions - one of the easier paths is to install it through
 `pipx <https://pypa.github.io/pipx/>`_ , which you can get from your distribution.

pyproject.toml

@@ -23,7 +23,7 @@ build-backend = "poetry.core.masonry.api"
 requires = ["poetry-core"]
 
 [tool.poetry.dependencies]
-python = "^3.11"
+python = "~3.11"
 attrs = "^23.1.0"
 dynaconf = "^3.2.4"
 factory_boy = "^3.2.1"