[KYUUBI #5105][Bug] getColumns gets duplicate column names when Spark integrates with Iceberg

### _Why are the changes needed?_

close #5105

### _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.readthedocs.io/en/master/contributing/code/testing.html#running-tests) locally before make a pull request

Closes #5128 from lsm1/features/kyuubi_5105.

Closes #5105

84be7fd6d [senmiaoliu] distinct default namespace

Authored-by: senmiaoliu <senmiaoliu@trip.com>
Signed-off-by: Cheng Pan <chengpan@apache.org>

externals/kyuubi-spark-sql-engine/src/main/scala/org/apache/kyuubi/engine/spark/util/SparkCatalogUtils.scala

@@ -137,7 +137,7 @@ object SparkCatalogUtils extends Logging {
     listAllNamespaces(catalog).filter { ns =>
       val quoted = ns.map(quoteIfNeeded).mkString(".")
       schemaPattern.r.pattern.matcher(quoted).matches()
-    }.distinct
+    }.map(_.toList).toList.distinct.map(_.toArray).toArray
   }
 
   private def getSchemasWithPattern(catalog: CatalogPlugin, schemaPattern: String): Seq[String] = {