fix: simplify logic

Author: diegomarquezp

sdk-platform-java/gax-java/gax/src/main/java/com/google/api/gax/tracing/SpanTracer.java

@@ -200,22 +200,27 @@ public void attemptPermanentFailure(Throwable error) {
   }
 
   private void recordErrorAndEndAttempt(Throwable error) {
-    if (attemptSpan != null) {
-      attemptSpan.setAttribute(
-          ObservabilityAttributes.ERROR_TYPE_ATTRIBUTE, ObservabilityUtils.extractErrorType(error));
-
-      if (error != null) {
-        attemptSpan.setAttribute(
-            ObservabilityAttributes.EXCEPTION_TYPE_ATTRIBUTE, error.getClass().getName());
+    if (attemptSpan == null) {
+      return;
+    }
 
-        String errorMessage = extractErrorMessage(error);
-        if (errorMessage != null) {
-          attemptSpan.setAttribute(ObservabilityAttributes.STATUS_MESSAGE_ATTRIBUTE, errorMessage);
-        }
-      }
+    attemptSpan.setAttribute(
+        ObservabilityAttributes.ERROR_TYPE_ATTRIBUTE, ObservabilityUtils.extractErrorType(error));
 
+    if (error == null) {
       endAttempt();
+      return;
     }
+
+    attemptSpan.setAttribute(
+        ObservabilityAttributes.EXCEPTION_TYPE_ATTRIBUTE, error.getClass().getName());
+
+    if (!Strings.isNullOrEmpty(error.getMessage())) {
+      attemptSpan.setAttribute(
+          ObservabilityAttributes.STATUS_MESSAGE_ATTRIBUTE, error.getMessage());
+    }
+
+    endAttempt();
   }
 
   private String extractErrorMessage(Throwable error) {