Depend on rack < 2

Rack 2.0 was released today and it requires Ruby 2.2+ now, which is
breaking Travis runs on anything that depends on Chef. This should get
our builds running again.

Signed-off-by: Tim Smith <tsmith@chef.io>

1 files changed, 1 insertions, 1 deletions

diff --git a/Gemfile b/Gemfile
index e2f4555af1..2437666bfe 100644
--- a/Gemfile
+++ b/Gemfile
@@ -65,7 +65,7 @@ end
 
 group(:development, :test) do
   gem "simplecov"
-  gem "rack"
+  gem "rack", "< 2.0"
 
   # for testing new chefstyle rules
   # gem 'chefstyle', github: 'chef/chefstyle'