change: removed unused libraries

Author: reeshika-h

src/test/java/com/contentstack/sdk/TestAssetLibrary.java

@@ -2,8 +2,6 @@
 
 import org.junit.jupiter.api.*;
 
-import com.google.gson.JsonObject;
-import org.json.*;
 
 import java.util.List;
 import java.util.logging.Logger;