Remove reference to Timecop from spec_helper.rb

Follow-up to #351

Now that `Timecop` has been removed, we no longer need to configure
RSpec to use it.

spec/features/new_project_spec.rb

@@ -271,11 +271,6 @@
     expect(gemfile).to match(/sassc-rails/)
   end
 
-  it "configures Timecop safe mode" do
-    spec_helper = read_project_file(%w[spec spec_helper.rb])
-    expect(spec_helper).to match(/Timecop.safe_mode = true/)
-  end
-
   it "adds and configures a bundler strategy for css and js" do
     gemfile = read_project_file("Gemfile")
 

templates/spec_helper.rb

@@ -1,5 +1,4 @@
 require "webmock/rspec"
-require "timecop"
 
 # http://rubydoc.info/gems/rspec-core/RSpec/Core/Configuration
 RSpec.configure do |config|
@@ -20,6 +19,3 @@
   allow_localhost: true,
   allow: "chromedriver.storage.googleapis.com"
 )
-
-# Only allow Timecop with block syntax
-Timecop.safe_mode = true