### _Why are the changes needed?_
It was reported in https://github.com/apache/kyuubi/discussions/4063
When run `SHOW DATABASES;` on Databricks Runtime, the error occurs
```
com.databricks.backend.common.rpc.SparkDriverExceptions$SQLExecutionException: java.lang.UnsupportedOperationException
at org.apache.spark.sql.catalyst.plans.logical.LeafNode.computeStats(LogicalPlan.scala:183)
at org.apache.spark.sql.catalyst.plans.logical.LeafNode.computeStats$(LogicalPlan.scala:183)
at org.apache.kyuubi.plugin.spark.authz.util.ObjectFilterPlaceHolder.computeStats(ObjectFilterPlaceHolder.scala:23)
at org.apache.spark.sql.catalyst.plans.QueryPlanStats.$anonfun$stats$1(QueryPlanStats.scala:39)
at scala.Option.getOrElse(Option.scala:189)
at org.apache.spark.sql.catalyst.plans.QueryPlanStats.stats(QueryPlanStats.scala:38)
at org.apache.spark.sql.catalyst.plans.QueryPlanStats.stats$(QueryPlanStats.scala:38)
at org.apache.spark.sql.catalyst.plans.logical.LogicalPlan.stats(LogicalPlan.scala:31)
```
### _How was this patch tested?_
- [x] 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#4076 from pan3793/stats.
Closes#4076
8238f317 [Cheng Pan] ut
a3c5f7d3 [Cheng Pan] [AUTHZ] Modified query plan should correctly report stats
Authored-by: Cheng Pan <chengpan@apache.org>
Signed-off-by: Cheng Pan <chengpan@apache.org>
71e46bd316