diff --git a/Gemfile.lock b/Gemfile.lock
index faffbf5..b2386d5 100644
--- a/Gemfile.lock
+++ b/Gemfile.lock
@@ -166,7 +166,9 @@ GEM
       net-smtp
     marcel (1.1.0)
     mini_mime (1.1.5)
-    minitest (5.26.1)
+    minitest (6.0.6)
+      drb (~> 2.0)
+      prism (~> 1.5)
     mocha (3.1.0)
       ruby2_keywords (>= 0.0.5)
     msgpack (1.8.0)
@@ -201,7 +203,7 @@ GEM
     pp (0.6.3)
       prettyprint
     prettyprint (0.2.0)
-    prism (1.4.0)
+    prism (1.9.0)
     psych (5.3.1)
       date
       stringio