added request_ids reference to job_guid description

treeherder/model/sql/template_schema/project_jobs_1.sql.tmpl

@@ -73,7 +73,7 @@ DROP TABLE IF EXISTS `job`;
  * Example Data:
  *
  *  job_guid - A unique identifier of a job or any type. For buildbot generated data
- *             the guid is a hash of associated result ids and a timestamp.
+ *             the guid is a hash of associated request_ids and a timestamp.
  *             
  *  job_coalesced_to_guid - If present the job was coalesced to this job_guid
  *  result_set_id - References result_set.id