fix workflow copy (#7659)

Co-authored-by: caishunfeng <534328519@qq.com>

dolphinscheduler-service/src/main/java/org/apache/dolphinscheduler/service/process/ProcessService.java

@@ -2332,11 +2332,14 @@ public class ProcessService {
             processTaskRelationLog.setProcessDefinitionCode(processDefinitionCode);
             processTaskRelationLog.setProcessDefinitionVersion(processDefinitionVersion);
             if (taskDefinitionLogMap != null) {
-                TaskDefinitionLog taskDefinitionLog = taskDefinitionLogMap.get(processTaskRelationLog.getPreTaskCode());
-                if (taskDefinitionLog != null) {
-                    processTaskRelationLog.setPreTaskVersion(taskDefinitionLog.getVersion());
+                TaskDefinitionLog preTaskDefinitionLog = taskDefinitionLogMap.get(processTaskRelationLog.getPreTaskCode());
+                if (preTaskDefinitionLog != null) {
+                    processTaskRelationLog.setPreTaskVersion(preTaskDefinitionLog.getVersion());
+                }
+                TaskDefinitionLog postTaskDefinitionLog = taskDefinitionLogMap.get(processTaskRelationLog.getPostTaskCode());
+                if (postTaskDefinitionLog != null) {
+                    processTaskRelationLog.setPostTaskVersion(postTaskDefinitionLog.getVersion());
                 }
-                processTaskRelationLog.setPostTaskVersion(taskDefinitionLogMap.get(processTaskRelationLog.getPostTaskCode()).getVersion());
             }
             processTaskRelationLog.setCreateTime(now);
             processTaskRelationLog.setUpdateTime(now);