MAINTAINERS: Update nrf_hw_models project collaborators

Let's update this west module/project collaborators:
wopu-ot & thoh-ot have been out of the picture for these HW models for
quite a while now, while rugeGerritsen has been much more active.

Signed-off-by: Alberto Escolar Piedras <[email protected]>

Author: aescolar

MAINTAINERS.yml

@@ -5679,8 +5679,7 @@ West:
   maintainers:
     - aescolar
   collaborators:
-    - wopu-ot
-    - thoh-ot
+    - rugeGerritsen
   files: []
   labels:
     - "area: native port"