Disable test runner task when not running with testclusters (#45659)

buildSrc/src/main/groovy/org/elasticsearch/gradle/test/RestIntegTestTask.groovy

@@ -63,6 +63,7 @@ class RestIntegTestTask extends DefaultTask {
         boolean usesTestclusters = project.plugins.hasPlugin(TestClustersPlugin.class)
         if (usesTestclusters == false) {
             clusterConfig = project.extensions.create("${name}Cluster", ClusterConfiguration.class, project)
+            runner.outputs.doNotCacheIf("Caching is disabled when using ClusterFormationTasks", { true })
         } else {
             project.testClusters {
                 "$name" {