fix(sqllab): SqlJsonExecutionContext.query null pointer (#16997)
fix(sqllab): SqlJsonExecutionContext.query null pointer (#16997)


airbnb/caravel,apache/incubator-superset,airbnb/caravel,zhouyao1994/incubator-superset,apache/incubator-superset,apache/incubator-superset,zhouyao1994/incubator-superset,zhouyao1994/incubator-superset,zhouyao1994/incubator-superset,airbnb/caravel,airbnb/caravel,apache/incubator-superset,zhouyao1994/incubator-superset,apache/incubator-superset