Revert "bump the redis gem to 3.3.2"

This reverts commit 1962b61afd.

Change-Id: I16b5057a83da82e5a300a953a0899fcdc52f993c
Reviewed-on: https://gerrit.instructure.com/99476
Tested-by: Jenkins
Reviewed-by: Simon Williams <simon@instructure.com>
Product-Review: Cody Cutrer <cody@instructure.com>
QA-Review: Cody Cutrer <cody@instructure.com>

Gemfile.d/redis.rb

@@ -7,6 +7,6 @@ group :redis do
     gem 'redis-store', '1.2.0'
   end
 
-  gem 'redis', '3.3.2'
+  gem 'redis', '3.3.1'
   gem 'redis-scripting', '1.0.1'
 end