Update steering-board.yml

Author: rct225

_data/orgs/steering-board.yml

@@ -5,7 +5,7 @@ personnel:
   - l_sexton-kennedy
   - p_calafiura
   - s_campana
-  - p_koppenburg
+  - n_grieser
   - c_doglioni
   - kherner
   - tulika176