Unable to perform operations in one thread

I am getting this exception on my jenkins node slaw server. Any ideas please on what might be causing this? I cannot find information about this exception anywhere.

java.lang.UnsupportedOperationException: Cannot nest operations in the same thread. Each nested operation must run in its own thread.
    at org.gradle.internal.operations.DefaultBuildOperationWorkerRegistry.doStartOperation(DefaultBuildOperationWorkerRegistry.java:65)
    at org.gradle.internal.operations.DefaultBuildOperationWorkerRegistry.access$400(DefaultBuildOperationWorkerRegistry.java:30)
    at org.gradle.internal.operations.DefaultBuildOperationWorkerRegistry$DefaultOperation.operationStart(DefaultBuildOperationWorkerRegistry.java:163)
    at org.gradle.api.internal.tasks.testing.worker.ForkingTestClassProcessor.processTestClass(ForkingTestClassProcessor.java:68)
    at org.gradle.api.internal.tasks.testing.processors.RestartEveryNTestClassProcessor.processTestClass(RestartEveryNTestClassProcessor.java:47)
    at sun.reflect.NativeMethodAccessorImpl.invoke0(Native Method)
    at sun.reflect.NativeMethodAccessorImpl.invoke(NativeMethodAccessorImpl.java:62)
    at sun.reflect.DelegatingMethodAccessorImpl.invoke(DelegatingMethodAccessorImpl.java:43)
    at java.lang.reflect.Method.invoke(Method.java:498)
    at org.gradle.internal.dispatch.ReflectionDispatch.dispatch(ReflectionDispatch.java:35)
    at org.gradle.internal.dispatch.ReflectionDispatch.dispatch(ReflectionDispatch.java:24)
    at org.gradle.internal.dispatch.FailureHandlingDispatch.dispatch(FailureHandlingDispatch.java:29)
    at org.gradle.internal.dispatch.AsyncDispatch.dispatchMessages(AsyncDispatch.java:132)
    at org.gradle.internal.dispatch.AsyncDispatch.access$000(AsyncDispatch.java:33)
    at org.gradle.internal.dispatch.AsyncDispatch$1.run(AsyncDispatch.java:72)
    at org.gradle.internal.concurrent.ExecutorPolicy$CatchAndRecordFailures.onExecute(ExecutorPolicy.java:54)
    at org.gradle.internal.concurrent.StoppableExecutorImpl$1.run(StoppableExecutorImpl.java:40)
    at java.util.concurrent.ThreadPoolExecutor.runWorker(ThreadPoolExecutor.java:1142)
    at java.util.concurrent.ThreadPoolExecutor$Worker.run(ThreadPoolExecutor.java:617)
    at java.lang.Thread.run(Thread.java:745)
 FAILED

FAILURE: Build failed with an exception.

* What went wrong:
Some child operations have not yet completed.

      

        
        
        
      

    

Reading this post, I updated it from Gradle v3.2.1 to v3.4 and the problem went away.