Revert "Update Sidekiq to 2.17.8"

This reverts commit 91ee82c5.

CHANGELOG

-v 7.5.3
-  - Update Sidekiq to version 2.17.8
+v 7.5.1
+  - Add missing timestamps to 'members' table
 v 7.5.2
   - Don't log Sidekiq arguments by default
   - Fix restore of wiki repositories from backups
-v 7.5.1
-  - Add missing timestamps to 'members' table
-
 v 7.5.0
   - API: Add support for Hipchat (Kevin Houdebert)
   - Add time zone configuration on gitlab.yml (Sullivan Senechal)

Gemfile

@@ -112,7 +112,7 @@ gem "acts-as-taggable-on"
 # Background jobs
 gem 'slim'
 gem 'sinatra', require: nil
-gem 'sidekiq', '2.17.8'
+gem 'sidekiq', '2.17.0'
 # HTTP requests
 gem "httparty"

Gemfile.lock

@@ -78,7 +78,7 @@ GEM
     coffee-script-source (1.6.3)
     colored (1.2)
     colorize (0.5.8)
-    connection_pool (2.1.0)
+    connection_pool (1.2.0)
     coveralls (0.7.0)
       multi_json (~> 1.3)
       rest-client
@@ -403,7 +403,7 @@ GEM
     rdoc (3.12.2)
       json (~> 1.4)
     redcarpet (3.1.2)
-    redis (3.1.0)
+    redis (3.0.6)
     redis-actionpack (4.0.0)
       actionpack (~> 4)
       redis-rack (~> 1.5.0)
@@ -411,8 +411,8 @@ GEM
     redis-activesupport (4.0.0)
       activesupport (~> 4)
       redis-store (~> 1.1.0)
-    redis-namespace (1.5.1)
-      redis (~> 3.0, >= 3.0.4)
+    redis-namespace (1.4.1)
+      redis (~> 3.0.4)
     redis-rack (1.5.0)
       rack (~> 1.5)
       redis-store (~> 1.1.0)
@@ -471,12 +471,12 @@ GEM
     sexp_processor (4.4.0)
     shoulda-matchers (2.1.0)
       activesupport (>= 3.0.0)
-    sidekiq (2.17.8)
-      celluloid (= 0.15.2)
-      connection_pool (~> 2.0)
+    sidekiq (2.17.0)
+      celluloid (>= 0.15.2)
+      connection_pool (>= 1.0.0)
       json
-      redis (~> 3.1)
-      redis-namespace (~> 1.3)
+      redis (>= 3.0.4)
+      redis-namespace (>= 1.3.1)
     simple_oauth (0.1.9)
     simplecov (0.9.0)
       docile (~> 1.1.0)
@@ -685,7 +685,7 @@ DEPENDENCIES
   semantic-ui-sass (~> 0.16.1.0)
   settingslogic
   shoulda-matchers (~> 2.1.0)
-  sidekiq (= 2.17.8)
+  sidekiq (= 2.17.0)
   simplecov
   sinatra
   six