History of Colour::class 1 change

In crates/hub/src/diffusion.rs, lines 245–254 on e8fa53694f686d9df2fe4805e81ceec44b0b5c90b56ac9a9be16f3ce8fec14ee. Every change that wrote or deleted one of these lines, or deleted a line from between them. Exact, because each line keeps its identity across edits; edits elsewhere in the file are not here. Also: oxy log -L 245,254:crates/hub/src/diffusion.rs.