Hi! I'm the developer of another quality related mod, Quality Assurance (https://mods.factorio.com/mod/QualityAssurance). On line 47 in data-updates.lua, you index a field called 'legendary-quality' which is nil. If this is the technology, then your mod is incompatible with Quality Assurance. Ways to fix this include: Only modifying the legendary quality technology in your data.lua file and checking for nils before trying to modify or access information about the legendary quality technology.
The full error can be see in the discussions tab where I was first notified about this: https://mods.factorio.com/mod/QualityAssurance/discussion/6748bb9926e562ccc06dc112