Remove unneeded check for Java 1.3+ in ShutdownHooks

It's unlikely anyone will be able to run JLine 3 on Java 1.2 or
lower.

terminal/src/main/java/org/jline/utils/ShutdownHooks.java

@@ -64,13 +64,7 @@ private static synchronized void runTasks() {
 
     private static Thread addHook(final Thread thread) {
         Log.debug("Registering shutdown-hook: ", thread);
-        try {
-            Runtime.getRuntime().addShutdownHook(thread);
-        }
-        catch (AbstractMethodError e) {
-            // JDK 1.3+ only method. Bummer.
-            Log.debug("Failed to register shutdown-hook", e);
-        }
+        Runtime.getRuntime().addShutdownHook(thread);
         return thread;
     }
 
@@ -98,10 +92,6 @@ private static void removeHook(final Thread thread) {
         try {
             Runtime.getRuntime().removeShutdownHook(thread);
         }
-        catch (AbstractMethodError e) {
-            // JDK 1.3+ only method. Bummer.
-            Log.debug("Failed to remove shutdown-hook", e);
-        }
         catch (IllegalStateException e) {
             // The VM is shutting down, not a big deal; ignore
         }
@@ -114,4 +104,4 @@ public interface Task
     {
         void run() throws Exception;
     }
-}
+}