History of JobGroup::drop 1 change

In crates/flow/src/syscall.rs, lines 428–437 on 72e9cfca63b535d6cef20a3169d7305da8548271fbd7e51691f3f6974a20671a. 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.