[KYUUBI #3711] PlanOnly should output engine logs to log files

### _Why are the changes needed?_

Fix https://github.com/apache/incubator-kyuubi/issues/3711
PlanOnly should output engine logs to log files so that they can be pulled from the front end.

### _How was this patch tested?_
- [ ] Add some test cases that check the changes thoroughly including negative and positive cases if possible

- [ ] Add screenshots for manual tests if appropriate

- [ ] [Run test](https://kyuubi.apache.org/docs/latest/develop_tools/testing.html#running-tests) locally before make a pull request

Closes #3712 from Yikf/planOnly-log-out.

Closes #3711

8469de9a [Yikf] planOnly should output engine logs to log files so that they can be pulled from the front end

Authored-by: Yikf <yikaifei1@gmail.com>
Signed-off-by: Cheng Pan <chengpan@apache.org>

externals/kyuubi-flink-sql-engine/src/main/scala/org/apache/kyuubi/engine/flink/operation/PlanOnlyStatement.scala

@@ -38,6 +38,11 @@ class PlanOnlyStatement(
   private val lineSeparator: String = System.lineSeparator()
   override def getOperationLog: Option[OperationLog] = Option(operationLog)
 
+  override protected def beforeRun(): Unit = {
+    OperationLog.setCurrentOperationLog(operationLog)
+    super.beforeRun()
+  }
+
   override protected def runInternal(): Unit = {
     try {
       val operation = executor.parseStatement(sessionId, statement)

externals/kyuubi-spark-sql-engine/src/main/scala/org/apache/kyuubi/engine/spark/operation/PlanOnlyStatement.scala

@@ -60,6 +60,11 @@ class PlanOnlyStatement(
     } else result.schema
   }
 
+  override protected def beforeRun(): Unit = {
+    OperationLog.setCurrentOperationLog(operationLog)
+    super.beforeRun()
+  }
+
   override protected def runInternal(): Unit = withLocalProperties {
     try {
       SQLConf.withExistingConf(spark.sessionState.conf) {