Merge branch '22466-task-list-fork' into 'master'

Resolve "Task List Checkbox Alignment"

## What does this MR do?

Replace the unmaintained `task_list` gem with the `deckar01-task_list` fork

## Are there points in the code the reviewer needs to double check?

 - I had to pin some dependencies in the fork to support `ruby < 2.2`, which added new version restrictions for 2 existing modules.
 - I triggered a build after I removed the patch to show the test passed with the new gem, then I removed the test, because this behavior is tested in the gem's repo now.

## Why was this MR needed?

 - The `task_list` patch was added with a comment that said it should be removed when merged upstream, but the repo got archived, so an upstream patch requires a fork.
 - #22470 can't be patched without warnings due to the way `task_list` uses Ruby constants.
 - There are additional outstanding `task_list` bugs that can be fixed once we switch to a fork.

## What are the relevant issue numbers?

 - #22466 
 - #22470
 - !6487

See merge request !6625

Gemfile

@@ -100,7 +100,7 @@ gem 'seed-fu', '~> 2.3.5'
 
 # Markdown and HTML processing
 gem 'html-pipeline',      '~> 1.11.0'
-gem 'task_list',     '~> 1.0.2', require: 'task_list/railtie'
+gem 'deckar01-task_list', '1.0.5', require: 'task_list/railtie'
 gem 'github-markup',      '~> 1.4'
 gem 'redcarpet',          '~> 3.3.3'
 gem 'RedCloth',           '~> 4.3.2'

Gemfile.lock

@@ -157,6 +157,10 @@ GEM
     database_cleaner (1.5.3)
     debug_inspector (0.0.2)
     debugger-ruby_core_source (1.3.8)
+    deckar01-task_list (1.0.5)
+      activesupport (~> 4.0)
+      html-pipeline
+      rack (~> 1.0)
     default_value_for (3.0.2)
       activerecord (>= 3.2.0, < 5.1)
     descendants_tracker (0.0.4)
@@ -725,8 +729,6 @@ GEM
       ffi
     sysexits (1.2.0)
     systemu (2.6.5)
-    task_list (1.0.2)
-      html-pipeline
     teaspoon (1.1.5)
       railties (>= 3.2.5, < 6)
     teaspoon-jasmine (2.2.0)
@@ -831,6 +833,7 @@ DEPENDENCIES
   creole (~> 0.5.0)
   d3_rails (~> 3.5.0)
   database_cleaner (~> 1.5.0)
+  deckar01-task_list (= 1.0.5)
   default_value_for (~> 3.0.0)
   devise (~> 4.2)
   devise-two-factor (~> 3.0.0)
@@ -963,7 +966,6 @@ DEPENDENCIES
   sprockets-es6 (~> 0.9.2)
   state_machines-activerecord (~> 0.4.0)
   sys-filesystem (~> 1.1.6)
-  task_list (~> 1.0.2)
   teaspoon (~> 1.1.0)
   teaspoon-jasmine (~> 2.2.0)
   test_after_commit (~> 0.4.2)

lib/banzai/filter/task_list_filter.rb

@@ -2,29 +2,7 @@ require 'task_list/filter'
 
 module Banzai
   module Filter
-    # Work around a bug in the default TaskList::Filter that adds a `task-list`
-    # class to every list element, regardless of whether or not it contains a
-    # task list.
-    #
-    # This is a (hopefully) temporary fix, pending a new release of the
-    # task_list gem.
-    #
-    # See https://github.com/github/task_list/pull/60
-    module ClassNamesFilter
-      def add_css_class(node, *new_class_names)
-        if new_class_names.include?('task-list')
-          # Don't add class to all lists
-          return
-        elsif new_class_names.include?('task-list-item')
-          super(node.parent, 'task-list')
-        end
-
-        super(node, *new_class_names)
-      end
-    end
-
     class TaskListFilter < TaskList::Filter
-      prepend ClassNamesFilter
     end
   end
 end

spec/lib/banzai/filter/task_list_filter_spec.rb

-require 'spec_helper'
-
-describe Banzai::Filter::TaskListFilter, lib: true do
-  include FilterSpecHelper
-
-  it 'does not apply `task-list` class to non-task lists' do
-    exp = act = %(<ul><li>Item</li></ul>)
-    expect(filter(act).to_html).to eq exp
-  end
-
-  it 'applies `task-list` to single-item task lists' do
-    act = filter('<ul><li>[ ] Task 1</li></ul>')
-
-    expect(act.to_html).to start_with '<ul class="task-list">'
-  end
-end