primitives: remove random_seed from BlockBuilder API (#8718)

* primitives: remove random_seed from BlockBuilderApi

* node: remove random_seed

* primitives: bump BlockBuilderApi version

* client: rpc: fix test

substrate/bin/node-template/runtime/src/lib.rs

@@ -367,10 +367,6 @@ impl_runtime_apis! {
 		) -> sp_inherents::CheckInherentsResult {
 			data.check_extrinsics(&block)
 		}
-
-		fn random_seed() -> <Block as BlockT>::Hash {
-			RandomnessCollectiveFlip::random_seed().0
-		}
 	}
 
 	impl sp_transaction_pool::runtime_api::TaggedTransactionQueue<Block> for Runtime {