Reinstate CI matrix

Author: georgesittas

.circleci/continue_config.yml

@@ -279,16 +279,16 @@ workflows:
           matrix:
             parameters:
               engine:
-                # - snowflake
+                - snowflake
                 - databricks
-                # - redshift
-                # - bigquery
-                # - clickhouse-cloud
-                # - athena
-          # filters:
-          #   branches:
-          #     only:
-          #       - main
+                - redshift
+                - bigquery
+                - clickhouse-cloud
+                - athena
+          filters:
+            branches:
+              only:
+                - main
       - trigger_private_tests:
           requires:
             - style_and_cicd_tests