Revert "Try to make some things work on my local system with Ruby newer than 2.6"

This reverts commit 98ce98d.

Author: ashak

Gemfile

@@ -11,6 +11,5 @@ group :development do
   gem 'pry'
   gem 'pry-byebug'
   gem 'rake', '10.1.0'
-  gem 'sync' if Gem::Version.new(RUBY_VERSION) > Gem::Version.new('2.6')
   gem 'syck' if RUBY_VERSION.split('.').first.to_i > 1
 end

Gemfile.lock

@@ -67,7 +67,6 @@ GEM
     ruby-progressbar (1.10.1)
     stomp (1.4.9)
     syck (1.4.0)
-    sync (0.5.0)
     systemu (2.6.5)
 
 PLATFORMS
@@ -86,7 +85,6 @@ DEPENDENCIES
   rspec (= 3.3.0)
   rubocop (= 0.32.1)
   syck
-  sync
 
 BUNDLED WITH
    1.17.3