message: docs: fix broken link in tracing-appender
diff: //! This creates an hourly rotating file appender that writes to `/some/directory/prefix.log.YYYY-MM-DD-HH`.
  //! [`Rotation::DAILY`] and [`Rotation::NEVER`] are the other available options.
  //!
  -//! The file appender implements [`std::io::Write`][write]. To be used with [`tracing_subscriber::FmtSubscriber`][fmt_subscrier],
  +//! The file appender implements [`std::io::Write`][write]. To be used with [`tracing_subscriber::FmtSubscriber`][fmt_subscriber],
  //! it must be combined with a [`MakeWriter`][make_writer] implementation to be able to record tracing spans/event.
  //!
  //! The [`rolling` module][rolling]'s documentation provides more detail on how to use this file appender.
  