Resolve variables for user-defined checks

[ssulca]

I would like use variables on user-defined checks queries, but it doesn't work.

# ${variable_name} doesn't work on user-defined checks queries

variables:
  TS_START: start date
  TS_END: end date 

checks for table:
  - count_column > 0 :
      count_column query: |
        select
           count(column)
        from "table"
        where created_at > '${TS_START}' and created_at < '${TS_END}'

resulting in

  |     cursor.execute(self.sql)
  | psycopg2.errors.InvalidDatetimeFormat: invalid input syntax for type timestamp: "${TS_START}"
  | LINE 4: where created_at > '${TS_START}' and created_at ...

[jmarien]

SODA-1012

[albinkjellin]

It would also be great if we can pass in variables to the standard checks as well like:

- row_count > ${row_count_threshold}:

[janet-can]

I believe the release of Soda Core 3.0.7 with a fix for 1577 resolves this issue. (Though the comment you made, @albinkjellin, is different and not resolved.