@Override
    public Supplier<AutoCloseable> hook() {
        return contextHook;
    }
Adds a hook which is invoked whenever this {@link NonWrappingRequestContext} is pushed to the
{@link RequestContextStorage}. The {@link AutoCloseable} returned by {@code contextHook} will be called
whenever this {@link RequestContext} is popped from the {@link RequestContextStorage}.
This method is useful when you need to propagate a custom context in this {@link RequestContext}'s scope.

<p>Note that this operation is highly performance-sensitive operation, and thus
it's not a good idea to run a time-consuming task.
core/src/main/java/com/linecorp/armeria/internal/common/NonWrappingRequestContext.java