Modularize tracing executor and metrics rename (#6424)

* Tracing executor and metrics rename

* Appease clippy

* Merge branch 'unstable' into modularise-task-executor

common/logging/src/lib.rs

@@ -1,6 +1,4 @@
-use lighthouse_metrics::{
-    inc_counter, try_create_int_counter, IntCounter, Result as MetricsResult,
-};
+use metrics::{inc_counter, try_create_int_counter, IntCounter, Result as MetricsResult};
 use slog::Logger;
 use slog_term::Decorator;
 use std::io::{Result, Write};

common/logging/src/tracing_metrics_layer.rs

@@ -1,6 +1,5 @@
 //! Exposes [`MetricsLayer`]: A tracing layer that registers metrics of logging events.
 
-use lighthouse_metrics as metrics;
 use std::sync::LazyLock;
 use tracing_log::NormalizeEvent;