As soon as the mod triggers to deploy, I get a crash. It doesn't happen when I have quality enabled.

Error while running event auto-deploy-combat-robots::on_nth_tick(60)
Unknown quality name: legendary
stack traceback:
[C]: in function 'remove_item'
auto-deploy-combat-robots/autodeploy.lua:8: in function '_deploy'
auto-deploy-combat-robots/autodeploy.lua:78: in function 'deploy_robots_for_player'
auto-deploy-combat-robots/autodeploy.lua:143: in function <auto-deploy-combat-robots/autodeploy.lua:141>

This would avoid the crash, but a dynamic list would be better if someone uses a mod with more/other quality levels.

local qualities = { "normal" }
if script.active_mods["quality"] then
qualities = {"legendary", "epic", "rare", "uncommon", "normal"}
end