Update extracts-built-in-roles.yaml

These seem like copy-paste errors.

Author: shannonbradshaw

source/includes/extracts-built-in-roles.yaml

@@ -127,7 +127,7 @@ content: |
 ---
 ref: built-in-roles-dbAdminAnyDatabase
 content: |
-  Provides the same read-only privileges as :authrole:`dbAdmin` on
+  Provides the same privileges as :authrole:`dbAdmin` on
   all databases except ``local`` and ``config``. The role also
   provides the :authaction:`listDatabases` action on the cluster as
   a whole.