History of supersede 2 changes

In crates/hub/src/flow.rs, lines 554–561 on 4b49c41599f3a29fdc805361569e0eaea120d7e96f1c6212bf7d7814f10481c3. 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 554,561:crates/hub/src/flow.rs.