Handle cleaning of zero-lamport accounts w.r.t. Incremental Snapshots (#18870)

* Handle cleaning zero-lamport accounts

Handle cleaning zero-lamport accounts in slots higher than the last full
snapshot slot.  This is part of the Incremental Snapshot work.

Fixes #18825

runtime/benches/accounts.rs

@@ -176,7 +176,7 @@ fn bench_delete_dependencies(bencher: &mut Bencher) {
         accounts.add_root(i);
     }
     bencher.iter(|| {
-        accounts.accounts_db.clean_accounts(None, false);
+        accounts.accounts_db.clean_accounts(None, false, None);
     });
 }