FIX: Sensitivity did not work by default

Forums without previously calculated scores would return the same values
for low/medium/high sensitivity. Now those are scaled based on the
default value.

The default value has also been changed from 10.0 to 12.5 based on
observing data from live discourse forums.

lib/post_action_creator.rb

@@ -155,6 +155,7 @@ private
   def auto_hide_if_needed
     return if @post.hidden?
     return if !@created_by.staff? && @post.user&.staff?
+    return unless PostActionType.auto_action_flag_types.include?(@post_action_name)
 
     # Special case: If you have TL3 and the user is TL0, and the flag is spam,
     # hide it immediately.
@@ -163,11 +164,11 @@ private
         @post.user&.trust_level == TrustLevel[0]
       @post.hide!(@post_action_type_id, Post.hidden_reasons[:flagged_by_tl3_user])
       return
-    elsif PostActionType.auto_action_flag_types.include?(@post_action_name)
-      score = ReviewableFlaggedPost.find_by(target: @post)&.score || 0
-      if score >= Reviewable.score_required_to_hide_post
-        @post.hide!(@post_action_type_id)
-      end
+    end
+
+    score = ReviewableFlaggedPost.find_by(target: @post)&.score || 0
+    if score >= Reviewable.score_required_to_hide_post
+      @post.hide!(@post_action_type_id)
     end
   end