Bom, 

Estou voltando a grails, depois de alguns anos, comecei a estudar Python e vi algumas comparações com Grails, e resolvi arriscar novamente ao grails.

Agora estou numa máquina Linux, e não consigo rodar nenhum projeto grails, está dando erro:

General error during semantic analysis: Unsupported class file major version 57
  
  java.lang.IllegalArgumentException: Unsupported class file major version 57

$ java -version
java version "13.0.2" 2020-01-14
Java(TM) SE Runtime Environment (build 13.0.2+8)
Java HotSpot(TM) 64-Bit Server VM (build 13.0.2+8, mixed mode, sharing)


$ grails -version
WARNING: An illegal reflective access operation has occurred
WARNING: Illegal reflective access by org.codehaus.groovy.vmplugin.v7.Java7$1 (file:/home/eduardocasa/.sdkman/candidates/grails/4.0.2/lib/org.codehaus.groovy/groovy/jars/groovy-2.5.6.jar) to constructor java.lang.invoke.MethodHandles$Lookup(java.lang.Class,int)
WARNING: Please consider reporting this to the maintainers of org.codehaus.groovy.vmplugin.v7.Java7$1
WARNING: Use --illegal-access=warn to enable warnings of further illegal reflective access operations
WARNING: All illegal access operations will be denied in a future release
| Grails Version: 4.0.2
| JVM Version: 13.0.2

$ gradle -version
------------------------------------------------------------
Gradle 6.3
------------------------------------------------------------
Build time:   2020-03-24 19:52:07 UTC
Revision:     bacd40b727b0130eeac8855ae3f9fd9a0b207c60
Kotlin:       1.3.70
Groovy:       2.5.10
Ant:          Apache Ant(TM) version 1.10.7 compiled on September 1 2019
JVM:          13.0.2 (Oracle Corporation 13.0.2+8)
OS:           Linux 5.3.0-46-generic amd64



Um outro detalhe, como eu elimino esses WARNING chato de mais.