Skip reindex tests from old es if we can't run it

Two of the versions of Elasticsearch we need to run for these tests
can't run in Java 9 so we skip the entire test if we are running in
java 9. For now. I'd like to reenable it to run against java 8 if
there is one available, but that can wait for another time.

Relates to #24561

qa/reindex-from-old/build.gradle

@@ -49,13 +49,19 @@ dependencies {
   es090 'org.elasticsearch:elasticsearch:0.90.13@zip'
 }
 
+if (project.javaVersion == JavaVersion.VERSION_1_9) {
+  /* We can't run the dependencies with Java 9 so for now we'll skip the whole
+   * thing. */
+  integTest.enabled = false
+} else {
   /* Set up tasks to unzip and run the old versions of ES before running the
    * integration tests. */
   for (String version : ['2', '1', '090']) {
     Task unzip = task("unzipEs${version}", type: Sync) {
       Configuration oldEsDependency = configurations['es' + version]
       dependsOn oldEsDependency
-    // Use a closure here to delay resolution of the dependency until we need it
+      /* Use a closure here to delay resolution of the dependency until we need
+       * it */
       from {
         oldEsDependency.collect { zipTree(it) }
       }
@@ -75,8 +81,9 @@ for (String version : ['2', '1', '090']) {
     integTest.dependsOn fixture
     integTestRunner {
       /* Use a closure on the string to delay evaluation until right before we
-     * run the integration tests so that we can be sure that the file is ready.
-     */
+       * run the integration tests so that we can be sure that the file is
+       * ready. */
       systemProperty "es${version}.port", "${ -> fixture.addressAndPort }"
     }
   }
+}