chore: rm cached bytes gauge (#3513)

crates/rpc/rpc/src/eth/cache.rs

@@ -512,9 +512,9 @@ where
         }
     }
 
+    #[inline]
     fn update_cached_metrics(&self) {
         self.metrics.cached_count.set(self.cache.len() as f64);
-        self.metrics.cached_bytes.set(self.cache.memory_usage() as f64);
     }
 }
 
@@ -584,8 +584,6 @@ where
 struct CacheMetrics {
     /// The number of entities in the cache.
     cached_count: Gauge,
-    /// The memory usage of the cache in bytes.
-    cached_bytes: Gauge,
     /// The number of queued consumers.
     queued_consumers_count: Gauge,
 }