Comment 1 for bug 1893463

Here's a branch that addresses this by adding a unique index on the report, folder, runner, run_time, and email fields of reporter.schedule: https://git.evergreen-ils.org/?p=working/Evergreen.git;a=shortlog;h=refs/heads/user/jboyer/lp1893463_uniq_recurrence / working/user/jboyer/lp1893463_uniq_recurrence

Clark is also taught that the specific error caused by this constraint is not a problem.