History of Credentials::fmt 1 change

In crates/oxy-strata/src/lib.rs, lines 78–86 on f6dccc4533c80e091e46c4defba12d9c29712a9fd6ec444457b5f75eb4882a94. 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 78,86:crates/oxy-strata/src/lib.rs.