[CredManUi] Style fixes

1. System bar colors to the spec described in the bug
2. Scrim color to lighter

Bug: 271478093
Test: manual (see bug for screenshot)
Change-Id: I424378881481909f4ae103cf518ce48e91806e20
diff --git a/packages/CredentialManager/Android.bp b/packages/CredentialManager/Android.bp
index 00d42bd..28b9bc0 100644
--- a/packages/CredentialManager/Android.bp
+++ b/packages/CredentialManager/Android.bp
@@ -20,6 +20,7 @@
     },
 
     static_libs: [
+        "PlatformComposeCore",
         "androidx.activity_activity-compose",
         "androidx.appcompat_appcompat",
         "androidx.compose.animation_animation-core",