Attempt to reproduce worker api logging problems

build.gradle

buildscript {
    repositories {
        mavenCentral()
    }

    dependencies {
        classpath("commons-io:commons-io:2.5")
        classpath("commons-codec:commons-codec:1.9")
    }
}

tasks.register('md5', CreateMD5) {
    destinationDirectory = project.layout.buildDirectory.dir('md5')
    source(project.layout.projectDirectory.file('src'))

    logging.captureStandardOutput(LogLevel.INFO)

    doFirst {
       println "should not see this!!!"
    }
}

import org.gradle.api.Action;
import org.gradle.api.file.RegularFile;
import org.gradle.api.provider.Provider;
import org.gradle.api.tasks.*;
import org.gradle.workers.*;
import org.gradle.api.file.DirectoryProperty;

import javax.inject.Inject;
import java.io.File;

abstract public class CreateMD5 extends SourceTask {

    @OutputDirectory
    abstract public DirectoryProperty getDestinationDirectory();

    @Inject
    abstract public WorkerExecutor getWorkerExecutor(); 

    @TaskAction
    public void createHashes() {
        WorkQueue workQueue = getWorkerExecutor().processIsolation(); 

        for (File sourceFile : getSource().getFiles()) {
            Provider<RegularFile> md5File = getDestinationDirectory().file(sourceFile.getName() + ".md5");
            workQueue.submit(GenerateMD5.class, parameters -> { 
                parameters.getSourceFile().set(sourceFile);
                parameters.getMD5File().set(md5File);
            });
        }
    }
}

import org.apache.commons.codec.digest.DigestUtils;
import org.apache.commons.io.FileUtils;
import org.gradle.workers.WorkAction;

import java.io.File;
import java.io.FileInputStream;
import java.io.InputStream;

public abstract class GenerateMD5 implements WorkAction<MD5WorkParameters> { 
    @Override
    public void execute() {
        try {
            File sourceFile = getParameters().getSourceFile().getAsFile().get();
            File md5File = getParameters().getMD5File().getAsFile().get();
            InputStream stream = new FileInputStream(sourceFile);
            System.out.println("Generating MD5 for " + sourceFile.getName() + "...");
            // Artificially make this task slower.
            Thread.sleep(3000);
            FileUtils.writeStringToFile(md5File, DigestUtils.md5Hex(stream), (String) null);
        } catch (Exception e) {
            throw new RuntimeException(e);
        }
    }
}

import org.gradle.api.file.RegularFileProperty;
import org.gradle.workers.WorkParameters;

public interface MD5WorkParameters extends WorkParameters {
    RegularFileProperty getSourceFile(); 
    RegularFileProperty getMD5File();
}