fix import

Author: Aleyna-B

backend/chat-app/src/test/java/com/aleynabenzer/ChatAppApplicationTests.java

@@ -2,6 +2,7 @@
 
 import org.junit.jupiter.api.Test;
 import org.springframework.boot.test.context.SpringBootTest;
+import com.aleynabenzer.chat.app.ChatAppApplication;
 
 @SpringBootTest(classes = ChatAppApplication.class)	//expicitly specify the application class bc the package names do not match
 class ChatAppApplicationTests {