chore(tox): add instructions for using pyenv with tox

Author: Pouyanpi

tox.ini

@@ -2,6 +2,11 @@
 # Poetry installs all the dependencies and the current package in editable mode.
 # Thus, tests are running against the local files and not the built and installed package
 # This is the recommended way to run tests with Poetry (https://python-poetry.org/docs/faq/#is-tox-supported)
+# How to use:
+# do
+# > pyenv install 3.9 3.10 3.11
+# > pyenv local 3.9 3.10 3.11
+
 [tox]
 envlist = py39, py310, py311