title: groovyx.net.http is missing RESTClient
body: <p>I'm trying to figure out how to use Spock for REST tests. The tutorials and examples I've found all use RESTClient.</p>
  <p>However I'm getting stuck with not being able to resolve RESTClient. The examples use <code>import groovyx.net.http.RESTClient</code>. According to the examples this RESTClient seems like it should be included in <code>org.codehaus.groovy.modules.http-builder</code>, which I've found in the MVN repository at <a href="https://mvnrepository.com/artifact/org.codehaus.groovy/http-builder/0.4.1" rel="nofollow noreferrer">https://mvnrepository.com/artifact/org.codehaus.groovy/http-builder/0.4.1</a>.</p>
  <p>0.4.1 seems to be the most recent version available there.
  This is my <code>build.gradle</code>:</p>
  <pre><code>plugins {
      id 'groovy'
      id 'java'
  }
  
  group 'org.example'
  version '1.0-SNAPSHOT'
  
  repositories {
      mavenCentral()
  }
  
  dependencies {
      implementation 'org.codehaus.groovy:groovy-all:3.0.8'
      implementation 'org.codehaus.groovy:http-builder:0.4.1'
      testImplementation 'org.junit.jupiter:junit-jupiter-api:5.6.0'
      testImplementation 'org.junit.jupiter:junit-jupiter-api:5.7.0'
      testRuntimeOnly 'org.junit.jupiter:junit-jupiter-engine'
      testRuntimeOnly 'org.junit.jupiter:junit-jupiter-engine:5.7.0'
      testImplementation 'org.spockframework:spock-core:2.0-groovy-3.0'
  
  }
  
  test {
      useJUnitPlatform()
  }
  </code></pre>
  <p>The import seems to find <code>groovyx.net.http</code>, but the code completion shows that there is no RESTClient in there.</p>
  <p>I also found an example <a href="https://stackoverflow.com/questions/26475643/groovyunable-to-resolve-class-groovyx-net-http-restclient">Groovy:unable to resolve class groovyx.net.http.RESTClient</a> which seem to be using <code>org.codehaus.groovy:http-builder:0.7</code>, but the <code>http://repository.codehaus.org/</code> isn't online anymore. When I insist on getting version 0.7, which I found is possible by using the solution suggested at <a href="https://stackoverflow.com/questions/32248317/building-oozie-unknown-host-repository-codehaus-org">building oozie: Unknown host repository.codehaus.org</a>, then the IntelliJ editor doesn't even find <code>groovyx</code> (it is highlighted red).</p>
  <p>I have to assume that the examples for making REST calls in Groovy that I found are showing obsolete material. Therefore the question is, what is the current best practice for making a REST call in Groovy? And in case it still is RESTClient, how can I get it to work?</p>