Update Sneakers.

Gemfile.lock

@@ -122,7 +122,7 @@ GEM
       sshkit (>= 1.6.1, != 1.7.0)
     almond-rails (0.0.3)
       rails (>= 4.2, < 6)
-    amq-protocol (2.0.1)
+    amq-protocol (2.2.0)
     arel (7.1.4)
     ast (2.3.0)
     autoprefixer-rails (6.7.6)
@@ -165,8 +165,8 @@ GEM
       sass (~> 3.3)
       sassy-maps (< 1.0.0)
     builder (3.2.3)
-    bunny (2.2.2)
-      amq-protocol (>= 2.0.1)
+    bunny (2.7.4)
+      amq-protocol (~> 2.2.0)
     byebug (9.0.6)
     cancancan (1.16.0)
     capistrano (3.6.1)
@@ -479,11 +479,11 @@ GEM
     sitemap_generator (5.2.0)
       builder (~> 3.0)
     slop (3.6.0)
-    sneakers (2.3.5)
-      bunny (~> 2.2.0)
+    sneakers (2.6.0)
+      bunny (~> 2.7.0)
+      concurrent-ruby (~> 1.0)
       serverengine (~> 1.5.11)
       thor
-      thread (~> 0.1.7)
     solr_wrapper (0.18.1)
       faraday
       ruby-progressbar
@@ -516,7 +516,6 @@ GEM
       diffy (~> 3.0)
       nokogiri (>= 1.3.2)
     thor (0.19.4)
-    thread (0.1.7)
     thread_safe (0.3.6)
     tilt (2.0.5)
     tins (1.12.0)
@@ -627,4 +626,4 @@ DEPENDENCIES
   webmock
 
 BUNDLED WITH
-   1.15.4
+   1.16.1

config/initializers/sneakers.rb

@@ -11,7 +11,7 @@
 
 WORKER_OPTIONS = {
   ack: true,
-  threads: 10,
+  threads: 5,
   prefetch: 10,
   timeout_job_after: 60,
   heartbeat: 5,