Add whitespace after copyright header

Add an additional lines after the copyright header and before the
`package` declaration. This aligns with the style used by Spring
Framework.

Issue gh-8945

itest/web/src/integration-test/java/org/springframework/security/integration/AbstractWebServerIntegrationTests.java

@@ -13,6 +13,7 @@
  * See the License for the specific language governing permissions and
  * limitations under the License.
  */
+
 package org.springframework.security.integration;
 
 import org.junit.After;

itest/web/src/integration-test/java/org/springframework/security/integration/BasicAuthenticationTests.java

@@ -13,6 +13,7 @@
  * See the License for the specific language governing permissions and
  * limitations under the License.
  */
+
 package org.springframework.security.integration;
 
 import org.junit.Test;

itest/web/src/integration-test/java/org/springframework/security/integration/ConcurrentSessionManagementTests.java

@@ -13,6 +13,7 @@
  * See the License for the specific language governing permissions and
  * limitations under the License.
  */
+
 package org.springframework.security.integration;
 
 import java.util.Collections;

itest/web/src/main/java/org/springframework/security/itest/web/TestController.java

@@ -13,6 +13,7 @@
  * See the License for the specific language governing permissions and
  * limitations under the License.
  */
+
 package org.springframework.security.itest.web;
 
 import org.springframework.web.bind.annotation.RequestMapping;