Ensure Coveralls is only used in a CI environment

Author: rastating

spec/spec_helper.rb

@@ -1,7 +1,12 @@
 # frozen_string_literal: true
 
+require 'simplecov'
 require 'coveralls'
-Coveralls.wear!
+
+SimpleCov.formatter = Coveralls::SimpleCov::Formatter if ENV['CI']
+SimpleCov.start do
+  add_filter 'db/migrations'
+end
 
 ENV['WPXF_ENV'] = 'test'