Drop CommunicationChannel::RETIRE_THRESHOLD to 1

Fixes CNVS-24308

Test plan:
 - Create a user
 - From a Rails console, run the following, where <id> is the
   newly created user's id:
     c = User.find(<id>).email_channel
     c.bounce_count = 1
     c.save!
 - Log in as the user
 - Visit the user's settings page
 - Ensure that a warning triangle shows up next to the user's
   email address on the right side of the page

Change-Id: Ibdd280ebd582c87e01f77e81917b3674810a6aba
Reviewed-on: https://gerrit.instructure.com/65804
Reviewed-by: Andrew Butterfield <abutterfield@instructure.com>
Tested-by: Jenkins
QA-Review: Adrian Russell <arussell@instructure.com>
Product-Review: Allison Weiss <allison@instructure.com>

app/models/communication_channel.rb

@@ -61,7 +61,7 @@ class CommunicationChannel < ActiveRecord::Base
   TYPE_PUSH     = 'push'
   TYPE_YO       = 'yo'
 
-  RETIRE_THRESHOLD = 3
+  RETIRE_THRESHOLD = 1
 
   # TODO: Will need to be internationalized. Also, do we want to allow this to be specified in a config file?
   def self.country_codes

spec/lib/notification_message_creator_spec.rb

@@ -300,12 +300,12 @@ describe NotificationMessageCreator do
 
     it "should not send to bouncing channels" do
       notification_set
-      @communication_channel.bounce_count = 1
+      @communication_channel.bounce_count = CommunicationChannel::RETIRE_THRESHOLD - 1
       @communication_channel.save!
       messages = NotificationMessageCreator.new(@notification, @assignment, :to_list => @user).create_message
       expect(messages.select{|m| m.to == 'value for path'}.size).to eq 1
 
-      @communication_channel.bounce_count = 100
+      @communication_channel.bounce_count = CommunicationChannel::RETIRE_THRESHOLD
       @communication_channel.save!
       messages = NotificationMessageCreator.new(@notification, @assignment, :to_list => @user).create_message
       expect(messages.select{|m| m.to == 'value for path'}.size).to eq 0

spec/models/communication_channel_spec.rb

@@ -293,7 +293,7 @@ describe CommunicationChannel do
         @cc1 = communication_channel_model(path: 'not_as_bouncy@example.edu')
         @cc2 = communication_channel_model(path: 'bouncy@example.edu')
 
-        %w{bouncy@example.edu Bouncy@example.edu bOuNcY@Example.edu bouncy@example.edu not_as_bouncy@example.edu bouncy@example.edu}.each do |path|
+        %w{bouncy@example.edu Bouncy@example.edu bOuNcY@Example.edu bouncy@example.edu bouncy@example.edu}.each do |path|
           CommunicationChannel.bounce_for_path(
             path: path,
             timestamp: nil,
@@ -304,7 +304,7 @@ describe CommunicationChannel do
         end
 
         @cc1.reload
-        expect(@cc1.bounce_count).to eq 1
+        expect(@cc1.bounce_count).to eq 0
         expect(@cc1.bouncing?).to be_falsey
 
         @cc2.reload
@@ -473,7 +473,7 @@ describe CommunicationChannel do
             @cc3 = communication_channel_model(path: 'BOUNCY@example.edu')
           end
 
-          %w{bouncy@example.edu Bouncy@example.edu bOuNcY@Example.edu bouncy@example.edu not_as_bouncy@example.edu bouncy@example.edu}.each do |path|
+          %w{bouncy@example.edu Bouncy@example.edu bOuNcY@Example.edu bouncy@example.edu bouncy@example.edu}.each do |path|
             CommunicationChannel.bounce_for_path(
               path: path,
               timestamp: nil,
@@ -484,7 +484,7 @@ describe CommunicationChannel do
           end
 
           @cc1.reload
-          expect(@cc1.bounce_count).to eq 1
+          expect(@cc1.bounce_count).to eq 0
           expect(@cc1.bouncing?).to be_falsey
 
           @cc2.reload