configuration: Consistency checks for PVF pre-checking (#4580)

As was suggested by Alexander Popiak [here][comment], this commit
checks the consistency of the configuration.

[comment]:
https://github.com/paritytech/polkadot/pull/4420#discussion_r764796519

polkadot/runtime/parachains/src/scheduler.rs

@@ -850,6 +850,10 @@ mod tests {
 			scheduling_lookahead: 2,
 			parathread_retries: 1,
 			pvf_checking_enabled: false,
+			// This field does not affect anything that scheduler does. However, `HostConfiguration`
+			// is still a subject to consistency test. It requires that `minimum_validation_upgrade_delay`
+			// is greater than `chain_availability_period` and `thread_availability_period`.
+			minimum_validation_upgrade_delay: 6,
 			..Default::default()
 		}
 	}