History of HubBackend::block 2 changes

In crates/hub/src/protocol.rs, lines 107–109 on 64e5964e9f132a1a209dd85292a1671d9324cd5cc3786d094ab12d18c9377f1e. 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 107,109:crates/hub/src/protocol.rs.