node 8 migration: remove warning on temporary unavailability (#6060)
node 8 migration: remove warning on temporary unavailability (#6060)

* remove warning on temporary unavailability
* format changes, update URL to use variable

yvonnewilson/docs,jeffreylees/docs,auth0/docs,yvonnewilson/docs,auth0/docs,auth0/docs,jeffreylees/docs,jeffreylees/docs,yvonnewilson/docs