History of supersede 2 changes

In crates/hub/src/flow.rs, lines 554–561 on d061ac87618c3b6171633725d2e7acf67af9c5cff5a70e860c88d1bde410fc74. 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.