Add extra unit test for AwsMetricAttributeGenerator

Author: harrryr

awsagentprovider/src/test/java/software/amazon/opentelemetry/javaagent/providers/AwsMetricAttributeGeneratorTest.java

@@ -632,6 +632,12 @@ public void testGetDBStatementRemoteOperation() {
     mockAttribute(DB_STATEMENT, "SELECT FROM *");
     mockAttribute(DB_OPERATION, "DB operation");
     validateExpectedRemoteAttributes("DB system", "DB operation");
+
+    // Case 10: Same as case 1 but with leading whitespace
+    mockAttribute(DB_SYSTEM, "DB system");
+    mockAttribute(DB_STATEMENT, "    SELECT DB statement");
+    mockAttribute(DB_OPERATION, null);
+    validateExpectedRemoteAttributes("DB system", "SELECT");
   }
 
   @Test