Also check sources duplicates, but only warn.

[github-actions[bot]]

Also check sources duplicates, but only warn. https://api.github.com/boozook/playdate/blob/44ba9bc18e094bd1efc0428025f6cd528c8bdf8b/cargo/src/assets/mod.rs#L195

Source of this issue

				}
			}

			// TODO: Also check sources duplicates, but only warn.
		}