[SPARK-15431][SQL][HOTFIX] ignore 'list' command testcase from CliSuite for now

## What changes were proposed in this pull request?
The test cases for  `list` command added in `CliSuite` by PR #13212 can not run in some jenkins jobs after being merged.
However, some jenkins jobs can pass:
https://amplab.cs.berkeley.edu/jenkins/job/spark-master-test-sbt-hadoop-2.6/
https://amplab.cs.berkeley.edu/jenkins/job/spark-master-test-sbt-hadoop-2.4/
https://amplab.cs.berkeley.edu/jenkins/job/spark-master-test-sbt-hadoop-2.2/
https://amplab.cs.berkeley.edu/jenkins/job/spark-master-test-sbt-hadoop-2.7/
https://amplab.cs.berkeley.edu/jenkins/job/spark-master-test-sbt-hadoop-2.3/

Others failed on this test case. But the failures on those jobs are at slightly different checkpoints among different jobs too. So it seems that CliSuite's output capture is flaky for list commands to check for expected output. There are test cases already in `HiveQuerySuite` and `SparkContextSuite` to cover the cases. So I am ignoring 2 test cases added by PR #13212 .

Author: Xin Wu <xinwu@us.ibm.com>

Closes #13276 from xwu0226/SPARK-15431-clisuite.

sql/hive-thriftserver/src/test/scala/org/apache/spark/sql/hive/thriftserver/CliSuite.scala

@@ -239,7 +239,7 @@ class CliSuite extends SparkFunSuite with BeforeAndAfterAll with Logging {
       "" -> "This is a test for Spark-11624")
   }
 
-  test("list jars") {
+  ignore("list jars") {
     val jarFile = Thread.currentThread().getContextClassLoader.getResource("TestUDTF.jar")
     runCliWithin(2.minute)(
       s"ADD JAR $jarFile" -> "",
@@ -248,7 +248,7 @@ class CliSuite extends SparkFunSuite with BeforeAndAfterAll with Logging {
     )
   }
 
-  test("list files") {
+  ignore("list files") {
     val dataFilePath = Thread.currentThread().getContextClassLoader
       .getResource("data/files/small_kv.txt")
     runCliWithin(2.minute)(