Are the Revenant rules official? If so which book are they in? [duplicate]

Critical Role spoiler ahead:

I have found the rules for this listed on Unearthed Arcana and homebrew sites but have the rules for Revenants been officially published as of yet? and What are the playable D&D races in 5e, and where can I find them?. lists as below:

Revenant (UA: "Gothic Heroes"), actually a subrace that can be applied to human, dragonborn, or tiefling

Does this, therefore, mean that Revenants are not official (come under the unofficial/official that UA rules do until they are published officially in a paid for book)