proxy ips to match tests, prevent fail for no proxies

config.yml.travis

@@ -14,5 +14,5 @@ logs_path: "/tmp/neocitiestestlogs"
 letsencrypt_key: ./tests/files/letsencrypt.key
 letsencrypt_endpoint: https://acme-staging.api.letsencrypt.org/
 proxy_ips:
-  - 127.0.0.1
-  - 127.0.0.2
+  - 10.0.0.1
+  - 10.0.0.2

workers/delete_cache_order_worker.rb

@@ -11,6 +11,8 @@ class DeleteCacheOrderWorker
     #proxy_ips = Resolv.getaddresses($config['cache_purge_ips_uri']).keep_if {|r| !r.match(/:/)}
     proxy_ips = $config['proxy_ips']
 
+    return if proxy_ips.nil? || proxy_ips.empty?
+
     proxy_ips.each do |proxy_ip|
       DeleteCacheWorker.perform_async proxy_ip, username, path
     end

workers/purge_cache_order_worker.rb

@@ -11,6 +11,8 @@ class PurgeCacheOrderWorker
     proxy_ips = $config['proxy_ips']
     #proxy_ips = Resolv.getaddresses($config['cache_purge_ips_uri']).keep_if {|r| !r.match(/:/)}
 
+    return if proxy_ips.nil? || proxy_ips.empty?
+
     proxy_ips.each do |proxy_ip|
       PurgeCacheWorker.perform_async proxy_ip, username, path
     end