History of Settings::usable 2 changes

In crates/hub/src/signin.rs, lines 100–102 on 05f1a85a284253adc4e796dba60b0a0556198b5e2be230687802a9a5ee3af821. 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 100,102:crates/hub/src/signin.rs.