Config for web3signer keep-alive (#5007)

* Allow tweaking connection pool settings

* Build docker image

* Fix imports

* Merge tag 'v4.6.0' into web3signer-keep-alive

v4.6.0

* Delete temp docker build stuff

* Fix tests

* Merge remote-tracking branch 'origin/unstable' into web3signer-keep-alive

* Update CLI text

validator_client/src/http_api/test_utils.rs

@@ -80,6 +80,7 @@ impl ApiTester {
         let initialized_validators = InitializedValidators::from_definitions(
             validator_defs,
             validator_dir.path().into(),
+            Default::default(),
             log.clone(),
         )
         .await

validator_client/src/http_api/tests.rs

@@ -68,6 +68,7 @@ impl ApiTester {
         let initialized_validators = InitializedValidators::from_definitions(
             validator_defs,
             validator_dir.path().into(),
+            Config::default(),
             log.clone(),
         )
         .await