validator/ cleanup (bp #12340) (#12352)

* validator/ cleanup

(cherry picked from commit 1a03afccb1)

# Conflicts:
#	core/src/validator.rs

* Move TestValidator into its own module

(cherry picked from commit 208dd1de3a)

# Conflicts:
#	core/src/validator.rs
#	tokens/tests/commands.rs

* Rebase

Co-authored-by: Michael Vines <mvines@gmail.com>

core/src/lib.rs

@@ -65,6 +65,7 @@ pub mod sigverify;
 pub mod sigverify_shreds;
 pub mod sigverify_stage;
 pub mod snapshot_packager_service;
+pub mod test_validator;
 pub mod tpu;
 pub mod transaction_status_service;
 pub mod tree_diff;