Unknown parameter "indexes" in derived table definition

Hello,

I’m using an off-shelf block for Jira. When I try to validate LookML, it shows a warning of ‘Unknown parameter “indexes” in derived table definition.’ I’ve checked the manual for indexes in derived table and the code seems following the instruction to exact. Any suggestion on potential fix here?

Thank you!

view: looker_calendar {

derived_table: {

persist_for: "24 hours"

  sql:

  SELECT

      DATEADD(day,CAST(numbers.number AS INT), '2013-01-01') as series_date

  FROM ${looker_numbers.SQL_TABLE_NAME} AS numbers ;;

  indexes: ["series_date"]

 }

}