attribute: implement fmt::Display

Instead of a custome to_str method
3 jobs from cleanup in 7 minutes and 44 seconds (queued for 2 seconds)
Status Job ID Name Coverage
  Test
passed #100367
fedora test

00:07:24

 
  Lint
manual #100369
allowed to fail manual
clippy
passed #100368
rustfmt

00:00:19