Bump version of poetry

Author: bobot

.github/actions/setup-poetry-env/action.yml

@@ -18,6 +18,7 @@ runs:
     - name: Install Poetry
       uses: snok/install-poetry@v1
       with:
+        version: 2.1.2
         virtualenvs-in-project: true
 
     - name: Load cached venv

README.md

@@ -27,7 +27,7 @@ source .venv/bin/activate
 Poetry is used for handling dependencies:
 
 ```
-pip install poetry
+pip install "poetry >=2.1.2"
 ```
 
 Finally, install the environment with