Keep route name for revisions consistent with node's

user_revision.links.task.yml

-entity.user.revisions:
-  route_name: entity.user.revisions
+entity.user.version_history:
+  route_name: entity.user.version_history
   base_route: entity.user.canonical
   title: 'Revisions'
   weight: 20

user_revision.routing.yml

-entity.user.revisions:
+entity.user.version_history:
   path: '/user/{user}/revisions'
   defaults:
     _title: 'Revisions'