History of HubBackend::block 2 changes

In crates/hub/src/protocol.rs, lines 45–47 on 9df855f299484650f651eb99c256626a8cf21052c88d5c6542357e532d6d814c. 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.