Typo: Bad UUIDv7 references in Section 4.5

[kyzer-davis]

This is already fixed in #14 but opening an issue to track until V02 is submitted to IETF since these are generating lots of feedback emails.

"4.5. UUIDv8 Layout and Bit Order":

Old:

   UUIDv8 SHOULD only be utilized if an implementation cannot utilize
   UUIDv1, UUIDv6, or UUIDv8.  Some situations in which UUIDv8 usage

New:

   UUIDv8 SHOULD only be utilized if an implementation cannot utilize
   UUIDv1, UUIDv6, or UUIDv7.  Some situations in which UUIDv8 usage

Thanks:
Ville Skyttä ville.skytta@iki.fi
Blachly, James James.Blachly@osumc.edu
Stefano Zuccaro zukrin@gmail.com