DOCSP-20779 remove see KB article verbiage and link (#654)

Author: ianf-mongodb

source/core/replica-set-arbiter.txt

@@ -63,10 +63,6 @@ contribute to the number of nodes in a replica set. When a replica set
 has multiple arbiters it is less likely that a majority of data bearing
 nodes will be available after a node failure.
 
-For more information, see this `Knowledge Base
-<https://kb.corp.mongodb.com/article/000019126/>`__ article on multiple
-arbiters.
-
 .. warning::
 
    If a secondary node falls behind the primary, and the cluster is