virtualenvs in readme

[BishopWolf]

Creating virtualenvs like described in the readme is not recommended at all. This will use the system Python, which could not be supported by Gate.

Instead the uv package can easy the task without relying on system's Python.
https://docs.astral.sh/uv/pip/environments/
https://medium.com/@vkmauryavk/managing-python-virtual-environments-with-uv-a-comprehensive-guide-ac74d3ad8dff

pip install uv
uv init
uv venv --python 3.12 opengate
uv activate opengate
uv pip install -U opengate

To deactivate, just do uv deactivate opengate

Also, to install anything, you just use uv pip install, always prepending uv to pip.