fix to multiple "add to library" toasts bug when adding a new series (#9433)

fix to multiple "add to library" toasts bug (#9177)

Co-authored-by: Houssein Zaghdane <zaghdane@fireflow.de>
(cherry picked from commit 6ce42dc1676fe0a2e553edbc004c05eb3fd5df45)

app/src/main/java/eu/kanade/tachiyomi/ui/manga/MangaScreenModel.kt

@@ -1085,6 +1085,9 @@ class MangaInfoScreenModel(
         }
 
         if (!isFavorited && !successState.hasPromptedToAddBefore) {
+            updateSuccessState { successState ->
+                successState.copy(hasPromptedToAddBefore = true)
+            }
             coroutineScope.launch {
                 val result = snackbarHostState.showSnackbar(
                     message = context.getString(R.string.snack_add_to_library),
@@ -1094,9 +1097,6 @@ class MangaInfoScreenModel(
                 if (result == SnackbarResult.ActionPerformed && !isFavorited) {
                     toggleFavorite()
                 }
-                updateSuccessState { successState ->
-                    successState.copy(hasPromptedToAddBefore = true)
-                }
             }
         }
     }