public static <T> T touch(T obj, @Nullable Object hint) {
        if (obj instanceof Bytes) {
            ((Bytes) obj).touch(hint);
        }
        return obj;
    }
Calls {@link ByteBuf#touch(Object)} on the specified {@link Bytes}'s underlying {@link ByteBuf}.
Does nothing if it's not a pooled {@link Bytes}.

@param obj maybe a pooled {@link Bytes} to touch its underlying {@link ByteBuf}
@param hint the hint to specify when calling {@link ByteBuf#touch(Object)}
core/src/main/java/com/linecorp/armeria/unsafe/PooledObjects.java