[fix] Fix the SERIAL_DISCARD execution_type not working (#10258)

* fix always stop process_instance when execution_type is SERIAL_DISCARD

* test: no running_process, submit it

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

@@ -333,10 +333,13 @@ public class ProcessServiceImpl implements ProcessService {
         } else if (processDefinition.getExecutionType().typeIsSerialDiscard()) {
             List<ProcessInstance> runningProcessInstances = this.processInstanceMapper.queryByProcessDefineCodeAndProcessDefinitionVersionAndStatusAndNextId(processInstance.getProcessDefinitionCode(),
                     processInstance.getProcessDefinitionVersion(), Constants.RUNNING_PROCESS_STATE, processInstance.getId());
-            if (CollectionUtils.isEmpty(runningProcessInstances)) {
+            if (CollectionUtils.isNotEmpty(runningProcessInstances)) {
                 processInstance.setState(ExecutionStatus.STOP);
                 saveProcessInstance(processInstance);
+                return;
             }
+            processInstance.setState(ExecutionStatus.SUBMITTED_SUCCESS);
+            saveProcessInstance(processInstance);
         } else if (processDefinition.getExecutionType().typeIsSerialPriority()) {
             List<ProcessInstance> runningProcessInstances = this.processInstanceMapper.queryByProcessDefineCodeAndProcessDefinitionVersionAndStatusAndNextId(processInstance.getProcessDefinitionCode(),
                     processInstance.getProcessDefinitionVersion(), Constants.RUNNING_PROCESS_STATE, processInstance.getId());

dolphinscheduler-service/src/test/java/org/apache/dolphinscheduler/service/process/ProcessServiceTest.java

@@ -421,7 +421,7 @@ public class ProcessServiceTest {
         Mockito.when(commandMapper.deleteById(7)).thenReturn(1);
         Mockito.when(processInstanceMapper.queryByProcessDefineCodeAndProcessDefinitionVersionAndStatusAndNextId(11L, 1, Constants.RUNNING_PROCESS_STATE, 224)).thenReturn(null);
         ProcessInstance processInstance8 = processService.handleCommand(logger, host, command7);
-        Assert.assertTrue(processInstance8 == null);
+        Assert.assertTrue(processInstance8 != null);
 
         ProcessDefinition processDefinition2 = new ProcessDefinition();
         processDefinition2.setId(123);