History of Settings::usable 2 changes

In crates/hub/src/signin.rs, lines 100–102 on acb8d109e981553b233a60ad4df83f8f868e9ecb88214c56cd927d7f4944a1a4. 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.