Fix the imports again.

Author: Aleksi Salmela

src/test/java/fi/helsinki/cs/tmc/cli/command/DownloadExercisesCommandTest.java

@@ -33,8 +33,8 @@
 import org.junit.runner.RunWith;
 import org.mockito.ArgumentCaptor;
 import org.powermock.core.classloader.annotations.PrepareForTest;
-import org.powermock.reflect.Whitebox;
 import org.powermock.modules.junit4.PowerMockRunner;
+import org.powermock.reflect.Whitebox;
 
 import java.io.File;
 import java.io.IOException;