Accept maintainer_note parameter in REST runner registration

What does this MR do and why?

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This MR adds support for taking in a maintainer_note field in the runner registration endpoint. A gitlab/gitlab-runner MR will soon take advantage from this addition so as to allow an admin to specify notes to be associated with the new runner.

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Part of #348299 (closed)

lib/tasks/gitlab/gitaly.rake

@@ -2,41 +2,6 @@
 
 namespace :gitlab do
   namespace :gitaly do
-    desc 'Installs gitaly for running tests within gitlab-development-kit'
-    task :test_install, [:dir, :storage_path, :repo] => :gitlab_environment do |t, args|
-      inside_gdk = Rails.env.test? && File.exist?(Rails.root.join('../GDK_ROOT'))
-
-      if ENV['FORCE_GITALY_INSTALL'] || !inside_gdk
-        Rake::Task["gitlab:gitaly:install"].invoke(*args)
-
-        next
-      end
-
-      gdk_gitaly_dir = ENV.fetch('GDK_GITALY', Rails.root.join('../gitaly'))
-
-      # Our test setup expects a git repo, so clone rather than copy
-      clone_repo(gdk_gitaly_dir, args.dir, clone_opts: %w[--depth 1]) unless Dir.exist?(args.dir)
-
-      # We assume the GDK gitaly already compiled binaries
-      build_dir = File.join(gdk_gitaly_dir, '_build')
-      FileUtils.cp_r(build_dir, args.dir)
-
-      # We assume the GDK gitaly already ran bundle install
-      bundle_dir = File.join(gdk_gitaly_dir, 'ruby', '.bundle')
-      FileUtils.cp_r(bundle_dir, File.join(args.dir, 'ruby'))
-
-      # For completeness we copy this for gitaly's make target
-      ruby_bundle_file = File.join(gdk_gitaly_dir, '.ruby-bundle')
-      FileUtils.cp_r(ruby_bundle_file, args.dir)
-
-      gitaly_binary = File.join(build_dir, 'bin', 'gitaly')
-      warn_gitaly_out_of_date!(gitaly_binary, Gitlab::GitalyClient.expected_server_version)
-    rescue Errno::ENOENT => e
-      puts "Could not copy files, did you run `gdk update`? Error: #{e.message}"
-
-      raise
-    end
-
     desc 'GitLab | Gitaly | Clone and checkout gitaly'
     task :clone, [:dir, :storage_path, :repo] => :gitlab_environment do |t, args|
       warn_user_is_not_gitlab
@@ -60,9 +25,6 @@ Usage: rake "gitlab:gitaly:install[/installation/dir,/storage/path]")
       storage_paths = { 'default' => args.storage_path }
       Gitlab::SetupHelper::Gitaly.create_configuration(args.dir, storage_paths)
 
-      # In CI we run scripts/gitaly-test-build
-      next if ENV['CI'].present?
-
       Dir.chdir(args.dir) do
         Bundler.with_original_env do
           env = { "RUBYOPT" => nil, "BUNDLE_GEMFILE" => nil }