History of HubBackend::block 2 changes

In crates/hub/src/protocol.rs, lines 59–61 on 119fd17d213f23e85f97bae161e490a8bcd9ed22b75c1374c58063a24fa6f670. 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.