diff --git a/01-docker-images/solution/demo/Gemfile.lock b/01-docker-images/solution/demo/Gemfile.lock
index 3de2c9e..2447787 100644
--- a/01-docker-images/solution/demo/Gemfile.lock
+++ b/01-docker-images/solution/demo/Gemfile.lock
@@ -42,8 +42,8 @@ GEM
       i18n (>= 0.7, < 2)
       minitest (~> 5.1)
       tzinfo (~> 1.1)
-    addressable (2.6.0)
-      public_suffix (>= 2.0.2, < 4.0)
+    addressable (2.8.0)
+      public_suffix (>= 2.0.2, < 5.0)
     archive-zip (0.12.0)
       io-like (~> 0.3.0)
     arel (9.0.0)
@@ -96,7 +96,9 @@ GEM
     marcel (0.3.3)
       mimemagic (~> 0.3.2)
     method_source (0.9.2)
-    mimemagic (0.3.3)
+    mimemagic (0.3.10)
+      nokogiri (~> 1)
+      rake
     mini_mime (1.0.2)
     mini_portile2 (2.4.0)
     minitest (5.11.3)
@@ -104,7 +106,7 @@ GEM
     nio4r (2.4.0)
     nokogiri (1.10.9)
       mini_portile2 (~> 2.4.0)
-    public_suffix (3.1.1)
+    public_suffix (4.0.6)
     puma (3.12.4)
     rack (2.0.8)
     rack-test (1.1.0)