Update icmi.yml (#947)

Extended deadlines, cf. https://icmi.acm.org/2025/important-dates/

Author: gdemelo

conference/HI/icmi.yml

@@ -20,8 +20,8 @@
         id: icmi25
         link: https://icmi.acm.org/2025/
         timeline:
-          - abstract_deadline: '2025-04-18 23:59:59'
-            deadline: '2025-04-25 23:59:59'
+          - abstract_deadline: '2025-04-25 23:59:59'
+            deadline: '2025-05-02 23:59:59'
         timezone: UTC+7
         date: Oct 13 - 17, 2025
         place: Canberra, Australia