Do not run configuration spec on travis

Author: pitr-ch

spec/concurrent/configuration_spec.rb

@@ -1,6 +1,6 @@
 module Concurrent
 
-  describe Configuration do
+  describe Configuration, notravis: true do
 
     before(:each) do
       # redundant - done in spec_helper.rb

spec/spec_helper.rb

@@ -37,9 +37,4 @@
 RSpec.configure do |config|
   #config.raise_errors_for_deprecations!
   config.order = 'random'
-
-  config.before(:each) do
-    #TODO: Better configuration management in individual test suites
-    reset_gem_configuration
-  end
 end