Add '@VisibleForTesting' to test-used ID arguments for clarity

feature/foryou/src/main/kotlin/com/google/samples/apps/nowinandroid/feature/foryou/navigation/ForYouNavigation.kt

@@ -16,6 +16,7 @@
 
 package com.google.samples.apps.nowinandroid.feature.foryou.navigation
 
+import androidx.annotation.VisibleForTesting
 import androidx.navigation.NavController
 import androidx.navigation.NavGraphBuilder
 import androidx.navigation.NavOptions
@@ -25,6 +26,7 @@ import androidx.navigation.navArgument
 import androidx.navigation.navDeepLink
 import com.google.samples.apps.nowinandroid.feature.foryou.ForYouRoute
 
+@VisibleForTesting
 const val LINKED_NEWS_RESOURCE_ID = "linkedNewsResourceId"
 const val FOR_YOU_ROUTE = "for_you_route/{$LINKED_NEWS_RESOURCE_ID}"
 private const val DEEP_LINK_URI_PATTERN =

feature/interests/src/main/kotlin/com/google/samples/apps/nowinandroid/feature/interests/navigation/InterestsNavigation.kt

@@ -16,6 +16,7 @@
 
 package com.google.samples.apps.nowinandroid.feature.interests.navigation
 
+import androidx.annotation.VisibleForTesting
 import androidx.navigation.NavController
 import androidx.navigation.NavGraphBuilder
 import androidx.navigation.NavOptions
@@ -24,6 +25,7 @@ import androidx.navigation.compose.composable
 import androidx.navigation.navArgument
 import com.google.samples.apps.nowinandroid.feature.interests.InterestsRoute
 
+@VisibleForTesting
 const val TOPIC_ID_ARG = "topicId"
 const val INTERESTS_ROUTE_BASE = "interests_route"
 const val INTERESTS_ROUTE = "$INTERESTS_ROUTE_BASE?$TOPIC_ID_ARG={$TOPIC_ID_ARG}"