Fix sql task will send alert if we don't choose the send email (#12984)

dolphinscheduler-task-plugin/dolphinscheduler-task-sql/src/main/java/org/apache/dolphinscheduler/plugin/task/sql/SqlTask.java

@@ -319,7 +319,7 @@ public class SqlTask extends AbstractTask {
         String result = resultJSONArray.isEmpty() ? JSONUtils.toJsonString(generateEmptyRow(resultSet))
                 : JSONUtils.toJsonString(resultJSONArray);
 
-        if (sqlParameters.getSendEmail() == null || sqlParameters.getSendEmail()) {
+        if (Boolean.TRUE.equals(sqlParameters.getSendEmail())) {
             sendAttachment(sqlParameters.getGroupId(), StringUtils.isNotEmpty(sqlParameters.getTitle())
                     ? sqlParameters.getTitle()
                     : taskExecutionContext.getTaskName() + " query result sets", result);