Reset the detachedVersion flag on upgrading cluster

This is needed so that the cluster is upgraded to the actual specified
version and not keep using the same detached version as before.
It has a limitation of not being able to upgrade to the detached
version, but there is no such test case currently.

Author: jozala

test/test-clusters/src/main/java/org/elasticsearch/test/cluster/local/DefaultLocalClusterHandle.java

@@ -167,13 +167,15 @@ public void upgradeNodeToVersion(int index, Version version) {
         Node node = nodes.get(index);
         node.stop(false);
         LOGGER.info("Upgrading node '{}' to version {}", node.getName(), version);
+        node.getSpec().setDetachedVersion(false);
         node.start(version);
         waitUntilReady();
     }
 
     @Override
     public void upgradeToVersion(Version version) {
         stop(false);
+        nodes.forEach(node -> node.getSpec().setDetachedVersion(false));
         if (started.getAndSet(true) == false) {
             LOGGER.info("Upgrading Elasticsearch test cluster '{}' to version {}", name, version);
             execute(() -> nodes.parallelStream().forEach(n -> n.start(version)));

test/test-clusters/src/main/java/org/elasticsearch/test/cluster/local/LocalClusterSpec.java

@@ -106,7 +106,7 @@ public static class LocalNodeSpec {
         private final List<String> jvmArgs;
         private final Path configDir;
         private Version version;
-        private final boolean detachedVersion;
+        private boolean detachedVersion;
 
         public LocalNodeSpec(
             LocalClusterSpec cluster,
@@ -179,6 +179,10 @@ public boolean isDetachedVersion() {
             return detachedVersion;
         }
 
+        public void setDetachedVersion(boolean detachedVersion) {
+            this.detachedVersion = detachedVersion;
+        }
+
         public List<User> getUsers() {
             return cluster.getUsers();
         }