Remove quotes from categories

Author: maresb

.github/workflows/ci.yml

@@ -45,8 +45,8 @@ jobs:
           environment-name: causalpy-test-${{ matrix.python-version }}
           cache-environment: true
           create-args: >-
-            --category "main"
-            --category "dev"
+            --category main
+            --category dev
       - name: Run doctests
         run: |
           pip install -e .[test]