Pin SystemUI-tests to Kotlin 1.9

SystemUI-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 SystemUI-tests
Change-Id: Ia741ba99cf702c2ac61e70d852c34b31b60a9f3b
diff --git a/packages/SystemUI/Android.bp b/packages/SystemUI/Android.bp
index 15f4e5a..38bd29a 100644
--- a/packages/SystemUI/Android.bp
+++ b/packages/SystemUI/Android.bp
@@ -774,6 +774,9 @@
     use_resource_processor: true,
     manifest: "tests/AndroidManifest-base.xml",
     resource_dirs: [],
+
+    kotlin_lang_version: "1.9",
+
     additional_manifests: ["tests/AndroidManifest.xml"],
     srcs: [
         "tests/src/**/*.kt",