clean imports and update package declaration

Author: deleonenriqueta

logback13/src/test/java/com/newrelic/logging/logback13/NewRelicLogback13Tests.java

@@ -3,13 +3,13 @@
  * SPDX-License-Identifier: Apache-2.0
  */
 
+package com.newrelic.logging.logback13;
+
 import ch.qos.logback.classic.Level;
 import ch.qos.logback.classic.Logger;
 import ch.qos.logback.classic.LoggerContext;
 import ch.qos.logback.classic.spi.ILoggingEvent;
 import ch.qos.logback.core.OutputStreamAppender;
-import com.newrelic.logging.logback13.NewRelicAsyncAppender;
-import com.newrelic.logging.logback13.NewRelicEncoder;
 import org.junit.jupiter.api.AfterEach;
 import org.junit.jupiter.api.BeforeEach;
 import org.junit.jupiter.api.Test;