move Chris S to alumni

(also got rid of some cruft for a previous alum)

Author: nlharris

_data/alumni.yml

@@ -54,15 +54,9 @@ members:
   name: Carlo Tornial
   orcid: 0000-0002-3734-1859
   wikidata: Q114403193
-- affiliation: La Jolla Institute for Immunology, La Jolla, CA
-  country: USA
-  departed: 2022-10-04
-  github: hectorguzor
-  groups:
-  - outreach
+- github: hectorguzor
   name: Hector Guzman-Orozco
   orcid: 0000-0003-3430-8997
-  wikidata: Q114354576
 - github: ramonawalls
   name: Ramona Walls
   orcid: 0000-0001-8815-0078
@@ -72,3 +66,7 @@ members:
   orcid: 0000-0001-8314-2140
   wikidata: Q52097457
   departed: 2025-05-01
+- github: cstoeckert
+  name: Chris Stoeckert
+  orcid: 0000-0002-5714-991X
+  departed: 2025-04-28