update Gemfile.lock

update Gemfile.lock

to fix Travis build

diff --git a/Gemfile.lock b/Gemfile.lock
index 1d7d616..6e66f89 100644
--- a/Gemfile.lock
+++ b/Gemfile.lock
@@ -1,7 +1,7 @@
 PATH
   remote: .
   specs:
-    onebox (1.8.82)
+    onebox (1.8.83)
       htmlentities (~> 4.3)
       moneta (~> 1.0)
       multi_json (~> 1.11)

GitHub sha: d0f99c5e

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