Remove instance vars access to several nuget services

Remove `attr_reader` statements
Replace them with reading `@XXX` vars directly

ee/app/presenters/packages/nuget/packages_metadata_presenter.rb

@@ -6,8 +6,6 @@ module Packages
       include API::Helpers::Packages::Nuget::MetadataPresenterHelpers
       include Gitlab::Utils::StrongMemoize
 
-      attr_reader :packages
-
       COUNT = 1.freeze
 
       def initialize(packages)
@@ -56,7 +54,7 @@ module Packages
 
       def sorted_versions
         strong_memoize(:sorted_versions) do
-          versions = packages.map(&:version).compact
+          versions = @packages.map(&:version).compact
           VersionSorter.sort(versions)
         end
       end

ee/app/presenters/packages/nuget/packages_versions_presenter.rb

@@ -3,8 +3,6 @@
 module Packages
   module Nuget
     class PackagesVersionsPresenter
-      attr_reader :packages
-
       def initialize(packages)
         @packages = packages
       end

ee/app/presenters/packages/nuget/service_index_presenter.rb

@@ -5,8 +5,6 @@ module Packages
     class ServiceIndexPresenter
       include API::Helpers::RelatedResourcesHelpers
 
-      attr_reader :project
-
       SERVICE_VERSIONS = {
         download: %w[PackageBaseAddress/3.0.0],
         search: %w[SearchQueryService SearchQueryService/3.0.0-beta SearchQueryService/3.0.0-rc],
@@ -52,13 +50,13 @@ module Packages
       end
 
       def build_service_url(service_type)
-        base_path = api_v4_projects_packages_nuget_path(id: project.id)
+        base_path = api_v4_projects_packages_nuget_path(id: @project.id)
 
         full_path = case service_type
                     when :download
                       api_v4_projects_packages_nuget_download_package_name_package_version_package_filename_path(
                         {
-                          id: project.id,
+                          id: @project.id,
                           package_name: nil,
                           package_version: nil,
                           package_filename: nil
@@ -70,7 +68,7 @@ module Packages
                     when :metadata
                       api_v4_projects_packages_nuget_metadata_package_name_package_version_path(
                         {
-                          id: project.id,
+                          id: @project.id,
                           package_name: nil,
                           package_version: nil
                         },

ee/app/services/packages/nuget/metadata_extraction_service.rb

@@ -7,8 +7,6 @@ module Packages
 
       ExtractionError = Class.new(StandardError)
 
-      attr_reader :package_file_id
-
       XPATHS = {
         package_name: '//xmlns:package/xmlns:metadata/xmlns:id',
         package_version: '//xmlns:package/xmlns:metadata/xmlns:version'
@@ -30,7 +28,7 @@ module Packages
 
       def package_file
         strong_memoize(:package_file) do
-          ::Packages::PackageFile.find_by_id(package_file_id)
+          ::Packages::PackageFile.find_by_id(@package_file_id)
         end
       end
 

ee/app/services/packages/nuget/update_package_from_metadata_service.rb

@@ -7,8 +7,6 @@ module Packages
 
       InvalidMetadataError = Class.new(StandardError)
 
-      attr_reader :package_file
-
       def initialize(package_file)
         @package_file = package_file
       end
@@ -16,10 +14,10 @@ module Packages
       def execute
         raise InvalidMetadataError.new('package name and/or package version not found in metadata') unless valid_metadata?
 
-        package_file.transaction do
-          package_file.update!(
+        @package_file.transaction do
+          @package_file.update!(
             file_name: package_filename,
-            file: package_file.file
+            file: @package_file.file
           )
 
           if existing_package_id
@@ -37,15 +35,15 @@ module Packages
       end
 
       def link_to_existing_package
-        package_to_destroy = package_file.package
-        package_file.update!(package_id: existing_package_id)
+        package_to_destroy = @package_file.package
+        @package_file.update!(package_id: existing_package_id)
         package_to_destroy.destroy!
       end
 
       def update_linked_package
         return unless package_name && package_version
 
-        package_file.package.update!(
+        @package_file.package.update!(
           name: package_name,
           version: package_version
         )
@@ -53,12 +51,12 @@ module Packages
 
       def existing_package_id
         strong_memoize(:existing_package_id) do
-          package_file.project.packages
-                              .nuget
-                              .with_name(package_name)
-                              .with_version(package_version)
-                              .pluck_primary_key
-                              .first
+          @package_file.project.packages
+                               .nuget
+                               .with_name(package_name)
+                               .with_version(package_version)
+                               .pluck_primary_key
+                               .first
         end
       end
 
@@ -72,7 +70,7 @@ module Packages
 
       def metadata
         strong_memoize(:metadata) do
-          ::Packages::Nuget::MetadataExtractionService.new(package_file.id).execute
+          ::Packages::Nuget::MetadataExtractionService.new(@package_file.id).execute
         end
       end