History of JobGroup::drop 1 change

In crates/flow/src/syscall.rs, lines 428–437 on 8b7034c55402f76dc7e7d545d7c86586791da15dc7414c8d212f1e8253d6b4d6. 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.