Fix Bundle config for gitaly bundle

`BUNDLE_FLAGS=--no-deployment` was not picked up
during bundle install in `tmp/tests/gitaly/ruby`.

As a result, `tmp/tests/gitaly/ruby` had `BUNDLE_DEPLOYMENT: "true"`.

This leads to default bundle path being `vendor/bundle`, instead of
using `GEM_HOME`

lib/tasks/gitlab/gitaly.rake

@@ -17,24 +17,29 @@ Usage: rake "gitlab:gitaly:install[/installation/dir,/storage/path]")
 
       checkout_or_clone_version(version: version, repo: args.repo, target_dir: args.dir, clone_opts: %w[--depth 1])
 
-      command = []
-      _, status = Gitlab::Popen.popen(%w[which gmake])
-      command << (status == 0 ? 'gmake' : 'make')
-
-      if Rails.env.test?
-        command.push(
-          'BUNDLE_FLAGS=--no-deployment',
-          "GEM_HOME=#{Bundler.bundle_path}")
-      end
-
       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
-        # In CI we run scripts/gitaly-test-build instead of this command
-        unless ENV['CI'].present?
-          Bundler.with_original_env { Gitlab::Popen.popen(command, nil, { "RUBYOPT" => nil, "BUNDLE_GEMFILE" => nil }) }
+        Bundler.with_original_env do
+          env = { "RUBYOPT" => nil, "BUNDLE_GEMFILE" => nil }
+
+          if Rails.env.test?
+            env["GEM_HOME"] = Bundler.bundle_path.to_s
+            env["BUNDLE_DEPLOYMENT"] = 'false'
+          end
+
+          Gitlab::Popen.popen([make_cmd], nil, env)
         end
       end
     end
+
+    def make_cmd
+      _, status = Gitlab::Popen.popen(%w[which gmake])
+      status == 0 ? 'gmake' : 'make'
+    end
   end
 end

spec/tasks/gitlab/gitaly_rake_spec.rb

@@ -41,6 +41,7 @@ RSpec.describe 'gitlab:gitaly namespace rake task' do
 
     describe 'checkout or clone' do
       before do
+        stub_env('CI', false)
         expect(Dir).to receive(:chdir).with(clone_path)
       end
 
@@ -86,18 +87,14 @@ RSpec.describe 'gitlab:gitaly namespace rake task' do
         end
 
         context 'when Rails.env is test' do
-          let(:command) do
-            %W[make
-               BUNDLE_FLAGS=--no-deployment
-               GEM_HOME=#{Bundler.bundle_path}]
-          end
+          let(:command) { %w[make] }
 
           before do
             stub_rails_env('test')
           end
 
-          it 'calls make in the gitaly directory with --no-deployment flag for bundle' do
-            expect(Gitlab::Popen).to receive(:popen).with(command, nil, { "BUNDLE_GEMFILE" => nil, "RUBYOPT" => nil }).and_return(true)
+          it 'calls make in the gitaly directory with BUNDLE_DEPLOYMENT and GEM_HOME variables' do
+            expect(Gitlab::Popen).to receive(:popen).with(command, nil, { "BUNDLE_GEMFILE" => nil, "RUBYOPT" => nil, "BUNDLE_DEPLOYMENT" => 'false', "GEM_HOME" => Bundler.bundle_path.to_s }).and_return(true)
 
             subject
           end