History of HubBackend::block 2 changes

In crates/hub/src/protocol.rs, lines 59–61 on 20b8fe85888b0cfd4f91c6884cbf43750f98a00daa52f0dd0cca7d40cc192ce6. 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 59,61:crates/hub/src/protocol.rs.