History of HubBackend::block 2 changes

In crates/hub/src/protocol.rs, lines 45–47 on 8a2dbcb56246f568de32a5360d2f8be66bb9704909ce1b5cebb1f3051863f33b. 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 45,47:crates/hub/src/protocol.rs.