Add import to PokerTest

exercises/poker/src/test/java/PokerTest.java

@@ -1,3 +1,11 @@
+import org.junit.Ignore;
+import org.junit.Test;
+
+import java.util.Arrays;
+import java.util.Collections;
+
+import static org.junit.Assert.assertEquals;
+
 public class PokerTest {
     @Test
     public void oneHand() {