Update octokit to 4.6.2

ChangeLog: https://github.com/octokit/octokit.rb/releases

Gemfile

@@ -328,7 +328,7 @@ end
 gem 'newrelic_rpm', '~> 3.16'
-gem 'octokit', '~> 4.3.0'
+gem 'octokit', '~> 4.6.2'
 gem 'mail_room', '~> 0.9.0'

Gemfile.lock

@@ -421,7 +421,7 @@ GEM
       multi_xml (~> 0.5)
       rack (>= 1.2, < 3)
     octokit (4.3.0)
-      sawyer (~> 0.7.0, >= 0.5.3)
+      sawyer (~> 0.8.0, >= 0.5.3)
     oj (2.17.4)
     omniauth (1.3.1)
       hashie (>= 1.2, < 4)
@@ -650,8 +650,8 @@ GEM
       sprockets (>= 2.8, < 4.0)
       sprockets-rails (>= 2.0, < 4.0)
       tilt (>= 1.1, < 3)
-    sawyer (0.7.0)
-      addressable (>= 2.3.5, < 2.5)
+    sawyer (0.8.1)
+      addressable (>= 2.3.5, < 2.6)
       faraday (~> 0.8, < 0.10)
     scss_lint (0.47.1)
       rake (>= 0.9, < 11)