That has been in the plugin for almost 12 months.
If the issue is arising now, it's something else causing it.
The plugin spawns 3 workbenches in the centre of the map (level 1, 2 and 3 bench), which is used for the Human_Workbench skill.
If the workbench is deleted, it is immediately re-created.
Someone may be using ent kill or remove to remove the entity, in which case it will continue to respawn.
If you want to disable it, you can disable the skill and they will not spawn, but I would get to the bottom of why they are being removed in the first place, because no other plugin should be touching them.