Fix NameError Admin::ApplicationSettings::UpdateService

What does this MR do?

When updating Admin application settings, I ran into this 500 error: NameError - uninitialized constant Admin::ApplicationSettings::UpdateService.

This is because app/controllers/admin/application_settings_controller.rb#perform_update is currently calling Admin::ApplicationSettings::UpdateService which does not exist, instead of ::ApplicationSettings::UpdateService. This MR fixes the 500 error by calling the correct class.

Processing by Admin::ApplicationSettingsController#reporting as HTML
  Parameters: {"authenticity_token"=>"[FILTERED]", "application_setting"=>{"recaptcha_enabled"=>"1", "login_recaptcha_protection_enabled"=>"1", "recaptcha_site_key"=>"[FILTERED]", "recaptcha_private_key"=>"[FILTERED]", "invisible_captcha_enabled"=>"0", "akismet_enabled"=>"0", "akismet_api_key"=>"[FILTERED]", "unique_ips_limit_enabled"=>"0", "unique_ips_limit_per_user"=>"10", "unique_ips_limit_time_window"=>"3600", "spam_check_endpoint_enabled"=>"0", "spam_check_endpoint_url"=>"", "spam_check_api_key"=>"[FILTERED]"}}

Completed 500 Internal Server Error in 137ms (ActiveRecord: 28.7ms | Elasticsearch: 0.0ms | Allocations: 61804)

NameError - uninitialized constant Admin::ApplicationSettings::UpdateService
Did you mean?  UpdateHighestRole:
  app/controllers/admin/application_settings_controller.rb:256:in `perform_update'

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Security

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