Add SensitiveUrl to redact user secrets from endpoints (#2326)

## Issue Addressed

#2276 

## Proposed Changes

Add the `SensitiveUrl` struct which wraps `Url` and implements custom `Display` and `Debug` traits to redact user secrets from being logged in eth1 endpoints, beacon node endpoints and metrics.

## Additional Info

This also includes a small rewrite of the eth1 crate to make requests using `Url` instead of `&str`. 
Some error messages have also been changed to remove `Url` data.

validator_client/src/http_api/tests.rs

@@ -11,12 +11,10 @@ use account_utils::{
 };
 use deposit_contract::decode_eth1_tx_data;
 use environment::null_logger;
-use eth2::{
-    lighthouse_vc::{http_client::ValidatorClientHttpClient, types::*},
-    Url,
-};
+use eth2::lighthouse_vc::{http_client::ValidatorClientHttpClient, types::*};
 use eth2_keystore::KeystoreBuilder;
 use parking_lot::RwLock;
+use sensitive_url::SensitiveUrl;
 use slashing_protection::{SlashingDatabase, SLASHING_PROTECTION_FILENAME};
 use slot_clock::TestingSlotClock;
 use std::marker::PhantomData;
@@ -33,7 +31,7 @@ type E = MainnetEthSpec;
 struct ApiTester {
     client: ValidatorClientHttpClient,
     initialized_validators: Arc<RwLock<InitializedValidators>>,
-    url: Url,
+    url: SensitiveUrl,
     _server_shutdown: oneshot::Sender<()>,
     _validator_dir: TempDir,
 }
@@ -117,7 +115,7 @@ impl ApiTester {
 
         tokio::spawn(async { server.await });
 
-        let url = Url::parse(&format!(
+        let url = SensitiveUrl::parse(&format!(
             "http://{}:{}",
             listening_socket.ip(),
             listening_socket.port()