Upgrade doorkeeper to 4.4.2 (#8321)

Gemfile.lock

@@ -181,7 +181,7 @@ GEM
     docile (1.3.0)
     domain_name (0.5.20180417)
       unf (>= 0.0.5, < 1.0.0)
-    doorkeeper (4.4.1)
+    doorkeeper (4.4.2)
       railties (>= 4.2)
     dotenv (2.2.2)
     dotenv-rails (2.2.2)
@@ -269,7 +269,7 @@ GEM
     httplog (1.0.2)
       colorize (~> 0.8)
       rack (>= 1.0)
-    i18n (1.0.1)
+    i18n (1.1.0)
       concurrent-ruby (~> 1.0)
     i18n-tasks (0.9.21)
       activesupport (>= 4.0.2)
@@ -347,7 +347,7 @@ GEM
       net-ssh (>= 2.6.5)
     net-ssh (4.2.0)
     nio4r (2.3.0)
-    nokogiri (1.8.2)
+    nokogiri (1.8.4)
       mini_portile2 (~> 2.3.0)
     nokogumbo (1.5.0)
       nokogiri
@@ -415,7 +415,7 @@ GEM
     puma (3.11.4)
     pundit (1.1.0)
       activesupport (>= 3.0.0)
-    rack (2.0.4)
+    rack (2.0.5)
     rack-attack (5.2.0)
       rack
     rack-cors (1.0.2)
@@ -423,7 +423,7 @@ GEM
       rack
     rack-proxy (0.6.4)
       rack
-    rack-test (1.0.0)
+    rack-test (1.1.0)
       rack (>= 1.0, < 3)
     rails (5.2.0)
       actioncable (= 5.2.0)
@@ -764,4 +764,4 @@ RUBY VERSION
    ruby 2.5.0p0
 
 BUNDLED WITH
-   1.16.2
+   1.16.3