Remove dependency_list usage counter

This counter counting usage by project, resulting in an ever growing
set in Redis as the feature gains adoption.

This data wasn't useful, while still consuming a relatively high
amount of memory, so we removed it.

A better approach would be using Redis HLL counters for this.

ee/app/controllers/projects/dependencies_controller.rb

@@ -18,8 +18,6 @@ module Projects
           render status: :ok
         end
         format.json do
-          ::Gitlab::UsageCounters::DependencyList.increment(project.id)
-
           render json: serializer.represent(dependencies, build: report_service.build)
         end
       end

ee/config/metrics/counts_all/20210216175211_dependency_list_usages_total.yml

@@ -7,7 +7,7 @@ product_stage: secure
 product_group: group::composition analysis
 product_category: dependency_scanning
 value_type: number
-status: active
+status: removed
 time_frame: all
 data_source: redis
 distribution:

ee/lib/ee/gitlab/usage_data.rb

@@ -201,7 +201,6 @@ module EE
             usage_data[:counts].merge!(
               {
                 confidential_epics: count(::Epic.confidential),
-                dependency_list_usages_total: redis_usage_data { ::Gitlab::UsageCounters::DependencyList.usage_totals[:total] },
                 epics: count(::Epic),
                 epic_issues: count(::EpicIssue),
                 geo_nodes: count(::GeoNode),

ee/lib/gitlab/usage_counters/dependency_list.rb

-# frozen_string_literal: true
-
-module Gitlab
-  module UsageCounters
-    class DependencyList < Common
-      def self.base_key
-        'DEPENDENCY_LIST_USAGE_COUNTER'
-      end
-    end
-  end
-end

ee/spec/controllers/projects/dependencies_controller_spec.rb

@@ -43,16 +43,6 @@ RSpec.describe Projects::DependenciesController do
           end
         end
 
-        context 'when usage ping is collected' do
-          let(:user) { developer }
-
-          it 'counts usage of the feature' do
-            expect(::Gitlab::UsageCounters::DependencyList).to receive(:increment).with(project.id)
-
-            get :index, params: params, format: :json
-          end
-        end
-
         context 'with existing report' do
           let_it_be(:pipeline) { create(:ee_ci_pipeline, :with_dependency_list_report, project: project) }
 

ee/spec/lib/ee/gitlab/usage_data_spec.rb

@@ -93,7 +93,6 @@ RSpec.describe Gitlab::UsageData do
         container_scanning_jobs
         coverage_fuzzing_jobs
         dast_jobs
-        dependency_list_usages_total
         dependency_scanning_jobs
         epics
         epics_deepest_relationship_level

ee/spec/lib/gitlab/usage_counters/dependency_list_spec.rb

-# frozen_string_literal: true
-
-require 'spec_helper'
-
-RSpec.describe Gitlab::UsageCounters::DependencyList, :clean_gitlab_redis_shared_state do
-  it_behaves_like 'a usage counter'
-end