Pin CarSystemUI-tests to Kotlin 1.9

CarSystemUI-tests fails to compile with Kotlin 2.0. Various
fixes can be made, but I leave it to the team to decided when and how
those fixes should be applied.

Kotlin 2 is not the current default in Android, but we are very
close.

Bug: 383569207
Flag: EXEMPT unflaggable
Test: m CarSystemUI-tests
Change-Id: Iceb986bc07b337c01e9001b4e8309214e30396d7
1 file changed