private static RequestContext unwrapTraceableRequestContext(RequestContext ctx) {
        while (true) {
            final RequestContext unwrapped = ctx.unwrap();
            if (!(unwrapped instanceof TraceableRequestContext)) {
                return unwrapped;
            }
            ctx = unwrapped;
        }
    }
Creates a new instance.

@param delegate the underlying {@link RequestContextStorage} that stores {@link RequestContext}
@param sampler the {@link Sampler} that determines whether to retain the stacktrace of the context leaks
core/src/main/java/com/linecorp/armeria/internal/common/LeakTracingRequestContextStorage.java