feat(postgres-driver): support CUBEJS_DB_SSL option

Author: paveltiunov

packages/cubejs-postgres-driver/driver/PostgresDriver.js

@@ -13,6 +13,7 @@ class PostgresDriver extends BaseDriver {
       port: process.env.CUBEJS_DB_PORT,
       user: process.env.CUBEJS_DB_USER,
       password: process.env.CUBEJS_DB_PASS,
+      ssl: process.env.CUBEJS_DB_SSL ? {} : undefined,
       ...config
     });
     const self = this;