How to modify jvm args

Hi anyone! I use MDK for 1.14.4 and I can't use old method of changing jvm argumets, for example:

runClient {

    args = ["--username=WantaSanchez"]
    jvmArgs "-Xms4G", "-Xmx4G", "-XX:+UnlockExperimentalVMOptions", "-XX:+UseG1GC", "-XX:G1NewSizePercent=20", "-XX:G1ReservePercent=20", "-XX:MaxGCPauseMillis=50", "-XX:G1HeapRegionSize=32M"
    
}

Now, in new Forge Gradle isn't working. So what I can use?