You know the logo file doesn't replace the Minecraft app icon, right?
It just shows in the mod info page.
Your earlier messages indicate you are aware of this even though your last message suggests otherwise.
This is examplemod.png in the root of src/main/resources showing in the mods listing:
If you tried this and it didn't work please provide your workspace in a GitHub repo.
If you're referring to BuildCraft robotics, which I see in the log, that looks like a pre-1.13 mod, please make sure you're only using mods designed for the same version of Minecraft that you're using.
Problem with BonsaiTrees2, also note that you are using at least one mod that was made for a different version of Minecraft from the one you are using.