Update CITATION.cff per review feedback

Co-authored-by: jpn-- <1036626+jpn--@users.noreply.github.com>

Author: Copilot

CITATION.cff

@@ -5,8 +5,6 @@ title: "ActivitySim"
 abstract: "Advanced, open-source, activity-based travel behavior modeling software based on best software development practices for distribution at no charge to the public."
 authors:
   - name: "Zephyr Foundation"
-    city: "Various"
-    country: "US"
 repository-code: "https://github.com/ActivitySim/activitysim"
 url: "https://activitysim.github.io/activitysim"
 license: BSD-3-Clause
@@ -18,7 +16,7 @@ keywords:
   - "travel demand modeling"
 preferred-citation:
   type: software
-  title: "ActivitySim: Activity-Based Travel Modeling"
+  title: "ActivitySim"
   authors:
     - name: "Zephyr Foundation"
   repository-code: "https://github.com/ActivitySim/activitysim"