sql: Fix task creation when providing a custom next_run value
Previously, it was not possible to create sequentially two oneshot tasks whose only differ by their next_run value.
Related to swh-web#4548 (closed)
Staging instance, all changes can be removed at any time
Previously, it was not possible to create sequentially two oneshot tasks whose only differ by their next_run value.
Related to swh-web#4548 (closed)