rust: remove excessive calls to `#[timed]`
This makes trace output *really* noisy and is only useful in case you want to
take a look at a single revlog.
This is easy to add back on a case-by-case basis and does not need to stay with
the more permanent timers.
edition = "2018"
max_width = 79
wrap_comments = true
error_on_line_overflow = true