feat: fix poetry shell with mise

poetry shell will add the venv python to the path but it'll be behind mise python(s)
so we tell the subshell not to auto-activate mise

ref: python-poetry/poetry#9463

functions/psh.fish

@@ -2,7 +2,7 @@ function psh -d "run pipenv/poetry shell (detects which one)"
     if [ -f Pipfile ]
         pipenv shell
     else if [ -f pyproject.toml ]
-        poetry shell
+        MISE_FISH_AUTO_ACTIVATE=0 poetry shell
     else
         echo "No Pipfile or pyproject.toml found"
     end