[hotfix][test] Changes the way the thread name of the ComponentMainTh…

…readExecutorServiceAdapter is created

The old implementation generated thread names having the prefix multiple times.

flink-runtime/src/test/java/org/apache/flink/runtime/concurrent/ComponentMainThreadExecutorServiceAdapter.java

@@ -78,7 +78,13 @@ public static ComponentMainThreadExecutor forSingleThreadExecutor(
             @Nonnull ScheduledExecutorService singleThreadExecutor) {
         final Thread thread =
                 CompletableFuture.supplyAsync(Thread::currentThread, singleThreadExecutor).join();
-        thread.setName(String.format("ComponentMainThread-%s", thread.getName()));
+        final String testMainThreadNamePrefix = "ComponentMainThread";
+        if (!thread.getName().contains(testMainThreadNamePrefix)) {
+            // we have to check the current name first because this instance can be reused as a
+            // ScheduledExecutorService
+            thread.setName(String.format("%s-%s", testMainThreadNamePrefix, thread.getName()));
+        }
+
         return new ComponentMainThreadExecutorServiceAdapter(singleThreadExecutor, thread);
     }