[SPARK-24531][TESTS] Remove version 2.2.0 from testing versions in HiveExternalCatalogVersionsSuite

## What changes were proposed in this pull request?

Removing version 2.2.0 from testing versions in HiveExternalCatalogVersionsSuite as it is not present anymore in the mirrors and this is blocking all the open PRs.

## How was this patch tested?

running UTs

Author: Marco Gaido <[email protected]>

Closes apache#21540 from mgaido91/SPARK-24531.

Author: mgaido91

sql/hive/src/test/scala/org/apache/spark/sql/hive/HiveExternalCatalogVersionsSuite.scala

@@ -195,7 +195,7 @@ class HiveExternalCatalogVersionsSuite extends SparkSubmitTestUtils {
 
 object PROCESS_TABLES extends QueryTest with SQLTestUtils {
   // Tests the latest version of every release line.
-  val testingVersions = Seq("2.0.2", "2.1.2", "2.2.0", "2.2.1", "2.3.0")
+  val testingVersions = Seq("2.0.2", "2.1.2", "2.2.1", "2.3.0")
 
   protected var spark: SparkSession = _