Handle worker timeouts configured as strings

This make sure that worker timeouts configured as a string don't break
the request duration calculation

changelogs/unreleased/bvl-fix-request-duration-calculation.yml

+---
+title: Handle worker timeouts configured as strings
+merge_request: 3877
+author:
+type: fixed

files/gitlab-cookbooks/gitlab/libraries/gitlab_rails.rb

@@ -246,7 +246,7 @@ module GitlabRails # rubocop:disable Style/MultilineIfModifier
       service = Services.enabled?('puma') ? 'puma' : 'unicorn'
       user_config = Gitlab[service]
       service_config = Gitlab['node']['gitlab'][service]
-      user_config['worker_timeout'] || service_config['worker_timeout']
+      (user_config['worker_timeout'] || service_config['worker_timeout']).to_i
     end
   end
 end unless defined?(GitlabRails) # Prevent reloading during converge, so we can test

spec/chef/recipes/gitlab-rails_spec.rb

@@ -1970,10 +1970,11 @@ describe 'gitlab::gitlab-rails' do
       using RSpec::Parameterized::TableSyntax
       where(:web_worker, :configured_timeout, :expected_duration) do
-        :unicorn | nil | 57
-        :unicorn | 30  | 29
-        :puma    | nil | 57
-        :puma    | 120 | 114
+        :unicorn | nil  | 57
+        :unicorn | 30   | 29
+        :unicorn | "30" | 29
+        :puma    | nil  | 57
+        :puma    | 120  | 114
       end
       with_them do