fix VERSION constant namespace module name

Author: nishidayuya

lib/omniauth/microsoft_graph/version.rb

@@ -1,4 +1,4 @@
-module Omniauth
+module OmniAuth
   module MicrosoftGraph
     VERSION = "0.3.3"
   end

omniauth-microsoft_graph.gemspec

@@ -5,7 +5,7 @@ require 'omniauth/microsoft_graph/version'
 
 Gem::Specification.new do |spec|
   spec.name          = "omniauth-microsoft_graph"
-  spec.version       = Omniauth::MicrosoftGraph::VERSION
+  spec.version       = OmniAuth::MicrosoftGraph::VERSION
   spec.authors       = ["Peter Philips", "Joel Van Horn"]
   spec.email         = ["pete@p373.net", "joel@joelvanhorn.com"]
   spec.summary       = %q{omniauth provider for Microsoft Graph}