Update the Select Interests presentation logic

Previously, we only show the Select Interests view (i.e., the tag
cloud) when the user has 0 tags.

Now that the backend auto-subscribes new users to the `dailyprompt`
tag, this change will cause them to see the Select Interests view
despite having subscribed to the dailyprompt tag.

WordPress/Classes/Extensions/Post+BloggingPrompts.swift

@@ -36,9 +36,9 @@ extension Post {
             """
     }
 
-    private enum Strings {
+    enum Strings {
         static let promptTag = "dailyprompt"
-        static let emptyParagraphBlock = """
+        fileprivate static let emptyParagraphBlock = """
         <!-- wp:paragraph -->
         <p></p>
         <!-- /wp:paragraph -->

WordPress/Classes/ViewRelated/Reader/ReaderInterestsCoordinator.swift

@@ -42,7 +42,17 @@ class ReaderSelectInterestsCoordinator {
                 return
             }
 
-            let isFollowingInterests = interests.count > 0
+            let isFollowingInterests = {
+                // New users are automatically subscribed to the 'dailyprompt' tag by default.
+                // Let's ignore this value and keep showing the Select Interests view if the user
+                // is not subscribed to any other tags.
+                if let interest = interests.first,
+                   interests.count == 1 {
+                    return interest.slug != Post.Strings.promptTag
+                }
+                return interests.count > 0
+            }()
+
             completion(isFollowingInterests)
         }
     }