fix(test): catch Throwable instead of Exception in concurrent registration test

TronError extends Error, not Exception, so use Throwable to ensure
worker thread failures are properly captured.

Co-Authored-By: Claude Opus 4.6 <noreply@anthropic.com>

Author: halibobo1205

framework/src/test/java/org/tron/core/utils/TransactionRegisterTest.java

@@ -56,7 +56,7 @@ public void testConcurrentAccessThreadSafe() throws InterruptedException {
       threads[i] = new Thread(() -> {
         try {
           TransactionRegister.registerActuator();
-        } catch (Exception e) {
+        } catch (Throwable e) {
           testPassed.set(false);
         }
       });