https://www.mkyong.com/spring-boot/spring-boot-how-to-disable-the-spring-logo-banner/

java -Dspring.main.banner-mode=off -jar boot-app.jar

package sample;

import org.springframework.boot.Banner;
import org.springframework.boot.CommandLineRunner;
import org.springframework.boot.SpringApplication;

public class Main implements CommandLineRunner {
    @Override
    public void run(String... args) throws Exception {
        //
    }

    public static void main(String [] args) {
        SpringApplication app = new SpringApplication(Main.class);
        app.setBannerMode(Banner.Mode.OFF); // OFF LOG
        SpringApplication.run(Main.class, args);
    }
}