test: Install Gitaly incrementally

In 08af0f9f (Speed up gitaly setup in tests, 2021-07-20) the setup of
Gitaly was sped up in test by copying it over from GDK whenever
possible. This drastically reduced the setup time, but it complicates
installations of Ruby gems in Gitaly.

This change rolls back that copy-from-GDK installation, but instead
incrementally installs Gitaly. So instead of removing tmp/tests/gitaly
completely and setting up from scratch, we now fetch the revision
specified in GITALY_SERVER_VERSION and trust `make` inside the Gitaly
directory to The Right Thing(tm).

Combined with the introduction of gitlab-development-kit@d2229da0
(Makefile: Stop nuking gitlab/tmp/tests/gitaly, 2021-12-06) this should
avoid Gitaly in test ever again would be built from scratch.

In case this would not work in some situations, we look at
FORCE_GITALY_INSTALL and if the environment variable is set
tmp/tests/gitaly is deleted before installing Gitaly again.

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

spec/support/helpers/test_env.rb

@@ -160,7 +160,8 @@ module TestEnv
     component_timed_setup('Gitaly',
       install_dir: gitaly_dir,
       version: Gitlab::GitalyClient.expected_server_version,
-      task: "gitlab:gitaly:test_install",
+      task: "gitlab:gitaly:install",
+      fresh_install: ENV.key?('FORCE_GITALY_INSTALL'),
       task_args: [gitaly_dir, repos_path, gitaly_url].compact) do
         Gitlab::SetupHelper::Gitaly.create_configuration(
           gitaly_dir,
@@ -522,7 +523,7 @@ module TestEnv
     end
   end
 
-  def component_timed_setup(component, install_dir:, version:, task:, task_args: [])
+  def component_timed_setup(component, install_dir:, version:, task:, fresh_install: true, task_args: [])
     start = Time.now
 
     ensure_component_dir_name_is_correct!(component, install_dir)
@@ -532,7 +533,7 @@ module TestEnv
 
     if component_needs_update?(install_dir, version)
       # Cleanup the component entirely to ensure we start fresh
-      FileUtils.rm_rf(install_dir)
+      FileUtils.rm_rf(install_dir) if fresh_install
 
       if ENV['SKIP_RAILS_ENV_IN_RAKE']
         # When we run `scripts/setup-test-env`, we take care of loading the necessary dependencies