Update test.yml

Author: bckohan

.github/workflows/test.yml

@@ -31,6 +31,7 @@ jobs:
     - name: Install Poetry
       uses: snok/install-poetry@v1
       with:
+        version: 1.5.1
         virtualenvs-create: true
         virtualenvs-in-project: true
     - name: Install Basic Dependencies