[ci] revert one shot-workers (elastic#22622)

* Revert "[CI] filter static versus ephemeral workers (elastic#22607)"
This reverts commit 5e21666.
* Revert "[CI] ensure one shot-worker (elastic#22588)"
This reverts commit 0a75258.

Jenkinsfile

@@ -211,7 +211,7 @@ def generateStages(Map args = [:]) {
 }
 
 def cloud(Map args = [:]) {
-  withNode(args.label) {
+  node(args.label) {
     startCloudTestEnv(name: args.directory, dirs: args.dirs)
   }
   withCloudTestEnv() {
@@ -226,7 +226,7 @@ def cloud(Map args = [:]) {
 def k8sTest(Map args = [:]) {
   def versions = args.versions
   versions.each{ v ->
-    withNode(args.label) {
+    node(args.label) {
       stage("${args.context} ${v}"){
         withEnv(["K8S_VERSION=${v}", "KIND_VERSION=v0.7.0", "KUBECONFIG=${env.WORKSPACE}/kubecfg"]){
           withGithubNotify(context: "${args.context} ${v}") {
@@ -271,7 +271,7 @@ def target(Map args = [:]) {
   def directory = args.get('directory', '')
   def withModule = args.get('withModule', false)
   def isMage = args.get('isMage', false)
-  withNode(args.label) {
+  node(args.label) {
     withGithubNotify(context: "${context}") {
       withBeatsEnv(archive: true, withModule: withModule, directory: directory, id: args.id) {
         dumpVariables()
@@ -681,25 +681,6 @@ def notifyBuildReason() {
   }
 }
 
-/**
-* Guarantee a specific worker can only be used for a specific build. This was not the case
-* with the customise node provisioner that reuses workers in some cases when there is a peak load.
-*/
-def withNode(def label, Closure body) {
-  def labels
-  // There are immutable workers and static ones, so the static ones are only metal, macosx and arm
-  if (label.contains('arm') || label.contains('macosx') || label.contains('metal')) {
-    labels = label
-  } else {
-    // Otherwise use the dynamic UUID for the gobld
-    def uuid = UUID.randomUUID().toString()
-    labels = label?.trim() ? "${label} && extra/${uuid}" : "extra/${uuid}"
-  }
-  node("${labels}") {
-    body()
-  }
-}
-
 /**
 * This class is the one used for running the parallel stages, therefore
 * its arguments are passed by the beatsStages step.