REGEXP_LIKE incompatible with SQL Server

[shishakovp-nih]

This problem was reported five months ago and fixed, but version 2.8.1 still has this issue.

Prev issue link:

• REGEXP_LIKE incompatible with SQL Server #897

Fix: 792d3aa

version 2.8.1 code:

https://github.com/celery/django-celery-beat/blob/v2.8.1/django_celery_beat/schedulers.py#L323

For some reason, it seems that this fix was lost or reverted.