Fix flaky test in ctl module

[ulysses-you]

Why are the changes needed?

As zookeeper mentioned, the result of getChildren is no guarantee order. So it is also no guarantee order that use exists children to create new node .

flaky test log:

- test expose zk service node to another namespace *** FAILED ***
  "...ceUri=localhost:1000[1];version=1.2.0;seque..." did not equal "...ceUri=localhost:1000[0];version=1.2.0;seque..." (ServiceControlCliSuite.scala:212)
  Analysis:
  "...ceUri=localhost:1000[1];version=1.2.0;seque..." -> "...ceUri=localhost:1000[0];version=1.2.0;seque..."

zookeeper description:

    /**
     * For the given znode path return the stat and children list.
     * <p>
     * If the watch is true and the call is successful (no exception is thrown),
     * a watch will be left on the node with the given path. The watch will be
     * triggered by a successful operation that deletes the node of the given
     * path or creates/delete a child under the node.
     * <p>
     * The list of children returned is not sorted and no guarantee is provided
     * as to its natural or lexical order.
     * <p>
     * A KeeperException with error code KeeperException.NoNode will be thrown
     * if no node with the given path exists.
     *
     * @since 3.3.0
     * 
     * @param path
     * @param watch
     * @param stat stat of the znode designated by path
     * @return an unordered array of children of the node with the given path
     * @throws InterruptedException If the server transaction is interrupted.
     * @throws KeeperException If the server signals an error with a non-zero
     *  error code.
     */
    public List<String> getChildren(String path, boolean watch, Stat stat)
            throws KeeperException, InterruptedException {
        return getChildren(path, watch ? watchManager.defaultWatcher : null,
                stat);
    }

How was this patch tested?

Pass CI.

[yaooqinn]

cc @turboFei

[codecov-commenter]

Codecov Report

Merging #653 (0be8248) into master (b09c87b) will increase coverage by 0.02%.
The diff coverage is n/a.

@@            Coverage Diff             @@
##           master     #653      +/-   ##
==========================================
+ Coverage   80.05%   80.07%   +0.02%     
==========================================
  Files         120      120              
  Lines        4693     4693              
  Branches      568      568              
==========================================
+ Hits         3757     3758       +1     
  Misses        611      611              
+ Partials      325      324       -1     

Impacted Files	Coverage Δ
.../scala/org/apache/kyuubi/server/KyuubiServer.scala	47.36% <0.00%> (-2.64%)	⬇️
...org/apache/spark/kyuubi/SQLOperationListener.scala	97.43% <0.00%> (+5.12%)	⬆️

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[turboFei]

thanks

[turboFei]

thanks, merged to master

[ulysses-you]

thanks , also merged to branch-1.2