Move test-validator to own module to reduce core dependencies (#20658)

* Move test-validator to own module to reduce core dependencies

* Fix a few TestValidator paths

* Use solana_test_validator crate for solana_test_validator bin

* Move client int tests to separate crate

Co-authored-by: Tyera Eulberg <tyera@solana.com>

validator/src/lib.rs

@@ -1,6 +1,6 @@
 #![allow(clippy::integer_arithmetic)]
-pub use solana_core::test_validator;
 pub use solana_gossip::cluster_info::MINIMUM_VALIDATOR_PORT_RANGE_WIDTH;
+pub use solana_test_validator;
 use {
     console::style,
     fd_lock::{RwLock, RwLockWriteGuard},