set CUBEJS_DB_MAX_POOL for Redshift Tests

Author: KSDaemon

packages/cubejs-testing-drivers/fixtures/redshift.json

@@ -24,6 +24,7 @@
       "CUBEJS_DB_NAME": "dev",
       "CUBEJS_DB_USER": "${DRIVERS_TESTS_CUBEJS_DB_REDSHIFT_USER}",
       "CUBEJS_DB_PASS": "${DRIVERS_TESTS_CUBEJS_DB_REDSHIFT_PASS}",
+      "CUBEJS_DB_MAX_POOL": "4",
 
       "CUBEJS_PG_SQL_PORT": "5656",
       "CUBEJS_SQL_USER": "admin",