arti: remove string slices

/// Configure a panic handler to send everything to tracing, in addition to our

/// default panic behavior.

#[allow(clippy::string_slice)] // TODO

fn install_panic_handler() {

    // TODO library support: There's a library called `tracing-panic` that

    // provides a hook we could use instead, but that doesn't have backtrace

        let msg = match panic_info.payload().downcast_ref::<&'static str>() {

            Some(s) => *s,

            None => match panic_info.payload().downcast_ref::<String>() {

                Some(s) => &s[..],

                Some(s) => s.as_str(),

                None => "Box<dyn Any>",

            },

        };