Review fixes for iceberg-1.8:testing (open-telemetry#18011)

Co-authored-by: otelbot <197425009+otelbot@users.noreply.github.com>

Author: otelbot[bot]

instrumentation/iceberg-1.8/testing/src/main/java/io/opentelemetry/instrumentation/iceberg/v1_8/AbstractIcebergTest.java

@@ -35,21 +35,21 @@
 import org.junit.jupiter.api.io.TempDir;
 
 abstract class AbstractIcebergTest {
-  protected static final int FORMAT_VERSION = 2;
-  protected static final Schema SCHEMA =
+  private static final int FORMAT_VERSION = 2;
+  private static final Schema SCHEMA =
       new Schema(
           NestedField.required(3, "id", IntegerType.get()),
           NestedField.required(4, "data", StringType.get()));
-  protected static final PartitionSpec SPEC =
+  private static final PartitionSpec SPEC =
       PartitionSpec.builderFor(SCHEMA).bucket("data", 16).build();
-  protected static final DataFile FILE_1 =
+  private static final DataFile FILE_1 =
       DataFiles.builder(SPEC)
           .withPath("/path/to/data-a.parquet")
           .withFileSizeInBytes(10L)
           .withPartitionPath("data_bucket=0")
           .withRecordCount(1L)
           .build();
-  protected static final DataFile FILE_2 =
+  private static final DataFile FILE_2 =
       DataFiles.builder(SPEC)
           .withPath("/path/to/data-b.parquet")
           .withFileSizeInBytes(10L)
@@ -58,8 +58,8 @@ abstract class AbstractIcebergTest {
           .withSplitOffsets(asList(1L))
           .build();
 
-  @TempDir protected File tableDir = null;
-  protected Table table;
+  @TempDir private File tableDir;
+  private Table table;
 
   protected abstract InstrumentationExtension testing();
 
@@ -386,7 +386,7 @@ private void assertSizeMetric(
                                                 expectedReport.tableName())))));
   }
 
-  static class SimpleReporter implements MetricsReporter {
+  private static class SimpleReporter implements MetricsReporter {
     private MetricsReport report;
 
     @Override