Missing dependency on amecsapi in fabric.mod.json

Because of this, Fabric treats it as an optional dependency and this means it may not be loaded. 

Declare it as a required dependency so that Amecs API does not silently fail to load because it's constraints were not met, such as the Fabric Loader version being too low. 

Checked https://www.curseforge.com/minecraft/mc-mods/amecs/files/6995329