Remove remaining use of rabl

Gemfile

@@ -11,7 +11,6 @@ gem 'hamster', '~> 3.0' # Thread-safe collection classes for Ruby
 gem 'parallel', '~> 1.17' # run processes in parallel
 gem 'puma_worker_killer', '~> 0.1.1' # TODO: Investigate why puma workers need to be killed.
 gem 'puma', '~> 4.0', '>= 4.0.1'
-gem 'rabl', '~> 0.14.1' # JSON serialization https://github.com/nesquena/rabl
 gem 'rake', '~> 12.3.2'
 gem 'sassc-rails', '~> 2.1', '>= 2.1.2'
 gem 'sassc', '~> 2.0', '>= 2.0.1'

Gemfile.lock

@@ -265,8 +265,6 @@ GEM
     puma_worker_killer (0.1.1)
       get_process_mem (~> 0.2)
       puma (>= 2.7, < 5)
-    rabl (0.14.1)
-      activesupport (>= 2.3.14)
     rack (2.2.2)
     rack-attack (5.4.2)
       rack (>= 1.0, < 3)
@@ -468,7 +466,6 @@ DEPENDENCIES
   puma (~> 4.0, >= 4.0.1)
   puma_worker_killer (~> 0.1.1)
   qx!
-  rabl (~> 0.14.1)
   rack-attack (~> 5.2)
   rack-ssl (~> 1.4)
   rack-timeout (~> 0.5.1)

NOTICE-ruby

@@ -3451,9 +3451,6 @@ Copyright (c) 2013 Michael Grosser <michael@grosser.it>
 ** parallel_tests; version 2.32.0 -- 
 ** puma_worker_killer; version 0.1.1 -- 
 ** qx; version 0.1.1 -- 
-** rabl; version 0.14.1 -- 
-Copyright (c) 2010 Nathan Esquenazi
-Copyright (c) 2011-2013 Nathan Esquenazi.
 ** rack; version 2.2.2 -- 
 Copyright (c) 2009-2018 Michael Fellinger <m.fellinger@gmail.com>
 Copyright (c) Django Software Foundation and individual contributors.

app/controllers/nonprofits/refunds_controller.rb

@@ -18,6 +18,7 @@ module Nonprofits
     def index
       charge = current_nonprofit.charges.find(params[:charge_id])
       @refunds = charge.refunds
+      render locals: {refunds: @refund}}
     end
 
 private

app/views/nonprofits/refunds/index.jbuilder

@@ -1,7 +1,6 @@
 # frozen_string_literal: true
 
 # License: AGPL-3.0-or-later WITH Web-Template-Output-Additional-Permission-3.0-or-later
-require 'rabl'
-Rabl.configure do |config|
-  config.enable_json_callbacks = true
-end
+json.data refunds do |refund|
+  json.extract refund, :id, :amount, :created_at, :reason, :comment
+end