Remove invalid iOS device from test list (#1572)

Author: a-maurice

scripts/gha/print_matrix_configuration.py

@@ -214,7 +214,6 @@
       # Slightly different OS versions because of limited FTL selection.
       {"type": "ftl", "device": "model=iphone13pro,version=15.7"},
       {"type": "ftl", "device": "model=iphone8,version=15.7"},
-      {"type": "ftl", "device": "model=ipadmini4,version=15.4"},
   ],
   "ios_latest": [
       {"type": "ftl", "device": "model=iphone14pro,version=16.6"},