History of Credentials::fmt 1 change

In crates/oxy-strata/src/lib.rs, lines 78–86 on c6e69e4b8d8f6fe6e7bec5dabc9d471c19c32bc457e05de8975a45100349af44. 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.