History of Pool::keep 2 changes

In crates/flow/src/cache.rs, lines 146–163 on 749d6e7168b8c8e305aeec116e4d0b7ec6e6ad589f9841c0f1524113ec2d61ab. 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 146,163:crates/flow/src/cache.rs.