History of Credentials::fmt 1 change

In crates/oxy-strata/src/lib.rs, lines 219–227 on 8b3c9b2ba502ddea79693377889fb5fb7504f46994b5f6a81728bfc661576d29. 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 219,227:crates/oxy-strata/src/lib.rs.