[KYUUBI-105]add a failover mode for kyuubi ha

[yaooqinn]

Is your feature request related to a problem? Please describe.

Kyuubi now supports load balance service mode for client to discover from a zookeeper namespace. In this mode, all kyuubi service instance uri in the namespace is randomly picked by the client itself.
The picked server will create a Spark application for this user(client). When this user create another client through zookeeper service discovery, there will be two very different situations. one is that the previous server is picked and the Spark application reused, the other one is that the previous server is not picked with a high probability and another Spark application will be created. This is good for large cluster which has enough resources. But for those cluster that are not well resourced, it is a waste to do so. When there're not enough resources to create a Spark application, the client will fail to create a session, which in fact should not happen.

Describe the solution you'd like

An Active/Standby mode may be able to overcome such a problem and still supply Kyuubi with high availability functions.

Describe alternatives you've considered

A clear and concise description of any alternative solutions or features you've considered.

Additional context

Add any other context or screenshots about the feature request here.

[codecov]

Codecov Report

Merging #106 into master will increase coverage by 1.14%.
The diff coverage is 82.24%.

@@             Coverage Diff              @@
##             master     #106      +/-   ##
============================================
+ Coverage     65.34%   66.48%   +1.14%     
- Complexity      447      475      +28     
============================================
  Files            67       71       +4     
  Lines          3353     3390      +37     
  Branches        487      487              
============================================
+ Hits           2191     2254      +63     
+ Misses          906      878      -28     
- Partials        256      258       +2

Impacted Files	Coverage Δ	Complexity Δ
...src/main/scala/yaooqinn/kyuubi/service/State.scala	100% <ø> (ø)	0 <0> (ø)	⬇️
...n/scala/yaooqinn/kyuubi/yarn/KyuubiAppMaster.scala	43.29% <0%> (-0.71%)	9 <0> (-1)
...r/src/main/scala/org/apache/spark/KyuubiConf.scala	99.54% <100%> (ø)	0 <0> (ø)	⬇️
...cala/yaooqinn/kyuubi/ha/ZooKeeperACLProvider.scala	100% <100%> (ø)	4 <4> (?)
.../main/scala/org/apache/spark/KyuubiSparkUtil.scala	97.19% <100%> (ø)	0 <0> (ø)	⬇️
...ain/scala/yaooqinn/kyuubi/ha/FailoverService.scala	50% <50%> (ø)	8 <8> (?)
...in/scala/yaooqinn/kyuubi/server/KyuubiServer.scala	94.87% <85.71%> (-2.28%)	10 <0> (+2)
...cala/yaooqinn/kyuubi/ha/HighAvailableService.scala	87.2% <87.2%> (ø)	7 <7> (?)
.../scala/yaooqinn/kyuubi/ha/LoadBalanceService.scala	91.66% <91.66%> (ø)	5 <5> (?)
...n/scala/yaooqinn/kyuubi/ha/JaasConfiguration.scala	94.73% <94.73%> (ø)	3 <3> (?)
... and 7 more

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