Update dshin-moz's availability for redmond-2026 F2F

Author: dshin-moz

planning/redmond-2026/index.md

@@ -100,6 +100,7 @@ Please list your availability in California time (morning/afternoon/all or speci
 | Stephen Chenney | EDT | 6am - 3pm | Some single hours not available |
 | Yehonatan Daniv | UTC+3 | preferably before 2 pm | Probably going to miss Wednesday (Passover eve) |
 | Roman Komarov | CEST | 9am-5pm | --- |
+| David Shin | EDT | 6am - 3pm | --- |
 
 ### Regrets