refactor in the test class

Signed-off-by: tnazarew <tomasz.nazarewicz@getindata.com>

Author: tnazarew

spark-bigquery-connector-common/src/test/java/com/google/cloud/spark/bigquery/util/GCPLabelUtilsTest.java

@@ -13,9 +13,6 @@
 import org.mockserver.model.Header;
 
 public class GCPLabelUtilsTest {
-  private ClientAndServer mockServer;
-  private String mockBaseUrl;
-
   public static final Header METADATA_HEADER = new Header("Metadata-Flavor", "Google");
   private static final String TEST_APP_NAME = "labels-test";
   private static final String TEST_APP_ID = "application_12345";
@@ -26,7 +23,6 @@ public class GCPLabelUtilsTest {
   private static final String TEST_SESSION_ID = "test-session";
   private static final String TEST_PROJECT_ID = "test-project";
   private static final String TEST_REGION = "us-central1";
-
   private static final ImmutableMap<String, String> EXPECTED_FACET_DATAPROC_CLUSTER =
       ImmutableMap.<String, String>builder()
           .put("job.uuid", TEST_RESOURCE_UUID)
@@ -56,6 +52,9 @@ public class GCPLabelUtilsTest {
           .put("region", TEST_REGION)
           .build();
 
+  private ClientAndServer mockServer;
+  private String mockBaseUrl;
+
   @Before
   public void setUp() {
     mockServer = ClientAndServer.startClientAndServer();