Fix OpenStruct use

Fixed OpenStruct use since Ruby 3 discourages it

Changelog: changed

.rubocop_manual_todo.yml

@@ -2608,7 +2608,6 @@ Style/OpenStructUse:
     - 'spec/lib/gitlab/gitaly_client/diff_stitcher_spec.rb'
     - 'spec/lib/gitlab/grape_logging/loggers/exception_logger_spec.rb'
     - 'spec/lib/gitlab/grape_logging/loggers/perf_logger_spec.rb'
-    - 'spec/lib/gitlab/grape_logging/loggers/queue_duration_logger_spec.rb'
     - 'spec/lib/gitlab/graphql/pagination/keyset/connection_generic_keyset_spec.rb'
     - 'spec/lib/gitlab/graphql/pagination/keyset/connection_spec.rb'
     - 'spec/lib/gitlab/legacy_github_import/project_creator_spec.rb'

spec/lib/gitlab/grape_logging/loggers/queue_duration_logger_spec.rb

@@ -9,7 +9,7 @@ RSpec.describe Gitlab::GrapeLogging::Loggers::QueueDurationLogger do
     let(:start_time) { Time.new(2018, 01, 01) }
 
     describe 'when no proxy time is available' do
-      let(:mock_request) { OpenStruct.new(env: {}) }
+      let(:mock_request) { double('env', env: {}) }
 
       it 'returns an empty hash' do
         expect(subject.parameters(mock_request, nil)).to eq({})
@@ -18,7 +18,7 @@ RSpec.describe Gitlab::GrapeLogging::Loggers::QueueDurationLogger do
 
     describe 'when a proxy time is available' do
       let(:mock_request) do
-        OpenStruct.new(
+        double('env',
           env: {
             'HTTP_GITLAB_WORKHORSE_PROXY_START' => (start_time - 1.hour).to_i * (10**9)
           }