[Kernel] Remove redundant imports and test suites (delta-io#2773)

## Description
Remove redundant imports and test suites.

Signed-off-by: Tai Le Manh <[email protected]>

Author: tlm365

kernel/kernel-defaults/src/test/java/io/delta/kernel/defaults/client/TestDefaultFileSystemClient.java

@@ -18,7 +18,6 @@ package io.delta.kernel.defaults
 import io.delta.golden.GoldenTableUtils.goldenTablePath
 
 import io.delta.kernel.defaults.utils.{TestRow, TestUtils}
-import io.delta.kernel.defaults.utils.DefaultKernelTestUtils.getTestResourceFilePath
 import org.apache.hadoop.conf.Configuration
 import org.scalatest.funsuite.AnyFunSuite
 

kernel/kernel-defaults/src/test/java/io/delta/kernel/defaults/client/TestDefaultJsonHandler.java

@@ -16,13 +16,14 @@
 package io.delta.kernel.defaults
 
 import java.math.{BigDecimal => BigDecimalJ}
+
 import scala.collection.JavaConverters._
+
 import io.delta.golden.GoldenTableUtils.goldenTablePath
 import io.delta.kernel.defaults.utils.{TestRow, TestUtils}
 import io.delta.kernel.expressions.{Column, Expression, Predicate}
 import io.delta.kernel.expressions.Literal._
 import io.delta.kernel.types._
-import org.apache.spark.sql.catalyst.plans.SQLHelper
 import org.scalatest.funsuite.AnyFunSuite
 
 class PartitionPruningSuite extends AnyFunSuite with TestUtils {

kernel/kernel-defaults/src/test/scala/io/delta/kernel/defaults/DeletionVectorSuite.scala

@@ -15,8 +15,6 @@
  */
 package io.delta.kernel.defaults.internal.expressions
 
-import java.util
-
 import io.delta.kernel.data.{ColumnarBatch, ColumnVector}
 import io.delta.kernel.defaults.internal.data.DefaultColumnarBatch
 import io.delta.kernel.defaults.utils.{TestUtils, VectorTestUtils}

kernel/kernel-defaults/src/test/scala/io/delta/kernel/defaults/PartitionPruningSuite.scala

@@ -35,7 +35,7 @@ import io.delta.kernel.internal.data.ScanStateRow
 import io.delta.kernel.internal.util.ColumnMapping
 import io.delta.kernel.internal.util.Utils.singletonCloseableIterator
 import io.delta.kernel.types._
-import io.delta.kernel.utils.{CloseableIterator, DataFileStatus}
+import io.delta.kernel.utils.CloseableIterator
 import org.apache.hadoop.conf.Configuration
 import org.apache.hadoop.shaded.org.apache.commons.io.FileUtils
 import org.apache.spark.sql.SparkSession