fix(database-service): use correct height key when fetching last comm…

…it (#802)

* fetch height by commit key

* Empty commit

* use #state.height

packages/database/source/database-service.ts

@@ -209,8 +209,7 @@ export class DatabaseService implements Contracts.Database.DatabaseService {
 			return [...this.#commitCache.values()].pop()!;
 		}
 
-		const height = this.blockIdStorage.getRange({ limit: 1, reverse: true }).asArray[0].value;
-		return await this.commitFactory.fromBytes(this.#readCommitBytes(height)!);
+		return await this.commitFactory.fromBytes(this.#readCommitBytes(this.#state.height)!);
 	}
 
 	public addCommit(commit: Contracts.Crypto.Commit): void {