Merge pull request #450 from ClickHouse/fix-449

fix missing database_engine error

Author: BentsiLeviav

dbt/adapters/clickhouse/relation.py

@@ -137,7 +137,7 @@ def create_from(
         else:
             # quoting is only available for non-source nodes
             cluster = quoting.credentials.cluster or ""
-            database_engine = quoting.credentials.database_engine
+            database_engine = quoting.credentials.database_engine or ""
 
         if (
             cluster