Install poetry from the new recommended source

Author: PeterJCLaw

.circleci/config.yml

@@ -5,7 +5,7 @@ references:
     run:
       name: Install Poetry
       command: |
-        curl -sSL https://raw.githubusercontent.com/python-poetry/poetry/master/get-poetry.py | python
+        curl -sSL https://install.python-poetry.org/ | python3
   restore-dependencies-cache: &restore-dependencies-cache
     restore_cache:
       keys: