FIX: Discobot mention tutorial should be case insensitive.

plugins/discourse-narrative-bot/lib/discourse_narrative_bot/actions.rb

@@ -69,7 +69,10 @@ module DiscourseNarrativeBot
       valid = false
 
       doc.css(".mention").each do |mention|
-        valid = true if mention.text == "@#{self.discobot_user.username}"
+        if mention.text.downcase == "@#{self.discobot_user.username}".downcase
+          valid = true
+          break
+        end
       end
 
       valid

plugins/discourse-narrative-bot/spec/discourse_narrative_bot/new_user_narrative_spec.rb

@@ -803,7 +803,7 @@ describe DiscourseNarrativeBot::NewUserNarrative do
 
       it 'should create the right reply' do
         post.update!(
-          raw: '@discobot hello how are you doing today?'
+          raw: '@disCoBot hello how are you doing today?'
         )
 
         narrative.expects(:enqueue_timeout_job).with(user)