Fix EE namespacing of DesignsCounterService

Although all tests were passing, SaveDesignsService would error when
attempting to increment the counter with:

    uninitialized constant EE::Gitlab::UsageCounters

ee/app/services/design_management/save_designs_service.rb

@@ -67,7 +67,7 @@ module DesignManagement
 
     def build_repository_action(file, design)
       action = new_file?(design) ? :create : :update
-      on_success { ::EE::Gitlab::UsageCounters::DesignsCounter.count(action) }
+      on_success { ::Gitlab::UsageCounters::DesignsCounter.count(action) }
 
       {
         action: action,

ee/lib/ee/gitlab/usage_data.rb

@@ -10,7 +10,7 @@ module EE
 
         override :usage_data_counters
         def usage_data_counters
-          super + [::EE::Gitlab::UsageCounters::DesignsCounter]
+          super + [::Gitlab::UsageCounters::DesignsCounter]
         end
 
         override :features_usage_data

ee/lib/gitlab/usage_counters/designs_counter.rb

 # frozen_string_literal: true
 
-module EE::Gitlab::UsageCounters
+module Gitlab::UsageCounters
   class DesignsCounter
     extend ::Gitlab::UsageDataCounters::RedisCounter
 

ee/spec/lib/ee/gitlab/usage_counters/designs_counter_spec.rb → ee/spec/lib/gitlab/usage_counters/designs_counter_spec.rb

@@ -2,7 +2,7 @@
 
 require 'spec_helper'
 
-describe EE::Gitlab::UsageCounters::DesignsCounter do
+describe Gitlab::UsageCounters::DesignsCounter do
   it_behaves_like 'a redis usage counter', 'Designs', :create
   it_behaves_like 'a redis usage counter', 'Designs', :update
   it_behaves_like 'a redis usage counter', 'Designs', :delete

ee/spec/services/design_management/save_designs_service_spec.rb

@@ -58,7 +58,7 @@ describe DesignManagement::SaveDesignsService do
         end
 
         it "updates the creation count" do
-          counter = EE::Gitlab::UsageCounters::DesignsCounter
+          counter = Gitlab::UsageCounters::DesignsCounter
           expect { service.execute }.to change { counter.read(:create) }.by(1)
         end
 
@@ -131,7 +131,7 @@ describe DesignManagement::SaveDesignsService do
           end
 
           it 'increments the update counter' do
-            counter = EE::Gitlab::UsageCounters::DesignsCounter
+            counter = Gitlab::UsageCounters::DesignsCounter
             expect { service.execute }.to change { counter.read(:update) }.by 1
           end
 
@@ -158,7 +158,7 @@ describe DesignManagement::SaveDesignsService do
           end
 
           it 'counts one creation and one update' do
-            counter = EE::Gitlab::UsageCounters::DesignsCounter
+            counter = Gitlab::UsageCounters::DesignsCounter
             expect { service.execute }
               .to change { counter.read(:create) }.by(1)
               .and change { counter.read(:update) }.by(1)
@@ -187,7 +187,7 @@ describe DesignManagement::SaveDesignsService do
           end
 
           it 'increments the creation count by 2' do
-            counter = EE::Gitlab::UsageCounters::DesignsCounter
+            counter = Gitlab::UsageCounters::DesignsCounter
             expect { service.execute }.to change { counter.read(:create) }.by 2
           end