test(android): Update API 35 headless app start expectation

Make the ApplicationStartInfo headless test install the listener that
now gates headless end-time resolution, matching the standalone path.

Co-authored-by: Cursor <cursoragent@cursor.com>

Author: buenaflor

sentry-android-core/src/test/java/io/sentry/android/core/performance/AppStartMetricsTestApi35.kt

@@ -112,7 +112,7 @@ class AppStartMetricsTestApi35 {
   }
 
   @Test
-  fun `known ApplicationStartInfo type without listener still handles headless app start`() {
+  fun `known ApplicationStartInfo type with listener handles headless app start`() {
     val mockStartInfo = mock<ApplicationStartInfo>()
     whenever(mockStartInfo.startupState).thenReturn(ApplicationStartInfo.STARTUP_STATE_STARTED)
     whenever(mockStartInfo.startType).thenReturn(ApplicationStartInfo.START_TYPE_WARM)
@@ -121,6 +121,7 @@ class AppStartMetricsTestApi35 {
     val metrics = AppStartMetrics.getInstance()
     metrics.appStartTimeSpan.setStartedAt(100)
     metrics.setClassLoadedUptimeMs(200)
+    metrics.setHeadlessAppStartListener {}
 
     val app = ApplicationProvider.getApplicationContext<Application>()
     metrics.registerLifecycleCallbacks(app)