Removed unused import.

Author: majusko

src/main/java/io/github/majusko/grpc/jwt/interceptor/AuthClientInterceptor.java

@@ -4,7 +4,6 @@
 import io.grpc.*;
 import org.slf4j.Logger;
 import org.slf4j.LoggerFactory;
-import sun.jvm.hotspot.debugger.ThreadContext;
 
 public class AuthClientInterceptor implements ClientInterceptor {