fix: remove unused imports

Author: dgawande12

src/test/java/com/factset/sdk/utils/authentication/ConfidentialClientTest.java

@@ -18,10 +18,6 @@
 import java.nio.file.Paths;
 import java.time.Duration;
 import java.util.*;
-import java.util.concurrent.CountDownLatch;
-import java.util.concurrent.TimeUnit;
-import java.util.concurrent.atomic.AtomicBoolean;
-import java.util.concurrent.atomic.AtomicReference;
 
 import static org.junit.jupiter.api.Assertions.*;
 import static org.mockito.Mockito.*;