No, Unfortunately, I do not find this attribute information in the connector’s official documentation but i think this is a standard attribute but can not confirm as believe it should be confirmed by SailPoint colleagues.
Although I found this post where the mention of same attribute is there one of the comments which you can check;
I addition to that I would suggest you to either check with SailPoint support regarding if we can use this attribute or may be just a give a quick try by adding some static attribute create policy and then add that attribute in this block in source json and see if AD provisioning is working fine. I also see in the above post that it is mentioned that we can use this attribute even in other connectors too so i think this could be helpful.
I hope this helps.
Regards
Vikas.