Allow newer minor releases of omniauth

Index: gitlab/Gemfile
===================================================================
--- gitlab.orig/Gemfile
+++ gitlab/Gemfile
@@ -21,7 +21,7 @@ gem "pg", '~> 0.18.2', group: :postgres
 gem 'devise',                 '~> 3.5.2'
 gem 'devise-async',           '~> 0.9.0'
 gem 'doorkeeper',             '~> 2.2.0'
-gem 'omniauth',               '~> 1.3.1'
+gem 'omniauth',               '~> 1.3', '>= 1.3.1'
 gem 'omniauth-azure-oauth2',  '~> 0.0.6'
 gem 'omniauth-bitbucket',     '~> 0.0.2'
 gem 'omniauth-cas3',          '~> 1.1.2'