History of JobGroup::drop 1 change

In crates/flow/src/syscall.rs, lines 428–437 on 010b9a79de79eb4178959198807865f560013c1e21d93b0ae32485d8dd945c4c. 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 428,437:crates/flow/src/syscall.rs.