Integrate tracing (#6339)

Tracing Integration
- [reference](5bbf1859e9/projects/project-ideas.md (L297))


  - [x] replace slog & log with tracing throughout the codebase
- [x] implement custom crit log
- [x] make relevant changes in the formatter
- [x] replace sloggers
- [x] re-write SSE logging components

cc: @macladson @eserilev

consensus/types/src/slot_epoch_macros.rs

@@ -227,17 +227,6 @@ macro_rules! impl_display {
                 write!(f, "{}", self.0)
             }
         }
-
-        impl slog::Value for $type {
-            fn serialize(
-                &self,
-                record: &slog::Record,
-                key: slog::Key,
-                serializer: &mut dyn slog::Serializer,
-            ) -> slog::Result {
-                slog::Value::serialize(&self.0, record, key, serializer)
-            }
-        }
     };
 }
 

consensus/types/src/test_utils/generate_deterministic_keypairs.rs

@@ -1,8 +1,8 @@
 use crate::*;
 use eth2_interop_keypairs::{keypair, keypairs_from_yaml_file};
-use log::debug;
 use rayon::prelude::*;
 use std::path::PathBuf;
+use tracing::debug;
 
 /// Generates `validator_count` keypairs where the secret key is derived solely from the index of
 /// the validator.