GraphQL query to fetch Epics fails when `sort` and `last` params are provided together

Summary

When fetching Epics list using GraphQL, Internal Server Error happens while running the query, following is the error trace;

ActiveRecord::IrreversibleOrderError (Order "start_date DESC NULLS LAST" cannot be reversed automatically):
  lib/gitlab/graphql/pagination/keyset/last_items.rb:17:in `take_items'
  lib/gitlab/graphql/pagination/keyset/connection.rb:113:in `block in limited_nodes'
  lib/gitlab/utils/strong_memoize.rb:30:in `strong_memoize'
  lib/gitlab/graphql/pagination/keyset/connection.rb:107:in `limited_nodes'
  lib/gitlab/graphql/pagination/keyset/connection.rb:100:in `nodes'
  lib/gitlab/graphql/authorize/authorize_field_service.rb:114:in `to_nodes'
  lib/gitlab/graphql/authorize/authorize_field_service.rb:87:in `block in filter_allowed'
  lib/gitlab/graphql/lazy.rb:17:in `block in then'
  lib/gitlab/graphql/lazy.rb:13:in `block in force'
  lib/gitlab/utils/strong_memoize.rb:30:in `strong_memoize'
  lib/gitlab/graphql/lazy.rb:13:in `force'
  lib/gitlab/graphql/generic_tracing.rb:48:in `with_labkit_tracing'
  lib/gitlab/graphql/generic_tracing.rb:30:in `platform_trace'
  lib/gitlab/graphql/generic_tracing.rb:48:in `with_labkit_tracing'
  lib/gitlab/graphql/generic_tracing.rb:30:in `platform_trace'
  lib/gitlab/graphql/generic_tracing.rb:48:in `with_labkit_tracing'
  lib/gitlab/graphql/generic_tracing.rb:30:in `platform_trace'
  app/graphql/gitlab_schema.rb:43:in `multiplex'
  app/graphql/gitlab_schema.rb:50:in `execute'
  app/controllers/graphql_controller.rb:71:in `execute_query'
  app/controllers/graphql_controller.rb:32:in `execute'
  ee/lib/gitlab/ip_address_state.rb:10:in `with'
  ee/app/controllers/ee/application_controller.rb:44:in `set_current_ip_address'
  app/controllers/application_controller.rb:493:in `set_current_admin'
  lib/gitlab/session.rb:11:in `with_session'
  app/controllers/application_controller.rb:484:in `set_session_storage'
  lib/gitlab/i18n.rb:73:in `with_locale'
  lib/gitlab/i18n.rb:79:in `with_user_locale'
  app/controllers/application_controller.rb:478:in `set_locale'
  lib/gitlab/error_tracking.rb:52:in `with_context'
  app/controllers/application_controller.rb:543:in `sentry_context'
  app/controllers/application_controller.rb:471:in `block in set_current_context'
  lib/gitlab/application_context.rb:54:in `block in use'
  lib/gitlab/application_context.rb:54:in `use'
  lib/gitlab/application_context.rb:21:in `with_context'
  app/controllers/application_controller.rb:463:in `set_current_context'
  lib/gitlab/metrics/elasticsearch_rack_middleware.rb:16:in `call'
  lib/gitlab/middleware/rails_queue_duration.rb:33:in `call'
  lib/gitlab/metrics/rack_middleware.rb:16:in `block in call'
  lib/gitlab/metrics/transaction.rb:61:in `run'
  lib/gitlab/metrics/rack_middleware.rb:16:in `call'
  lib/gitlab/request_profiler/middleware.rb:17:in `call'
  lib/gitlab/query_limiting/middleware.rb:17:in `block in call'
  lib/gitlab/query_limiting/transaction.rb:39:in `run'
  lib/gitlab/query_limiting/middleware.rb:16:in `call'
  lib/gitlab/jira/middleware.rb:19:in `call'
  lib/gitlab/middleware/go.rb:20:in `call'
  lib/gitlab/etag_caching/middleware.rb:13:in `call'
  lib/gitlab/middleware/multipart.rb:234:in `call'
  lib/gitlab/middleware/read_only/controller.rb:51:in `call'
  lib/gitlab/middleware/read_only.rb:18:in `call'
  lib/gitlab/middleware/same_site_cookies.rb:27:in `call'
  lib/gitlab/middleware/handle_malformed_strings.rb:19:in `call'
  lib/gitlab/middleware/basic_health_check.rb:25:in `call'
  lib/gitlab/middleware/handle_ip_spoof_attack_error.rb:25:in `call'
  lib/gitlab/middleware/request_context.rb:23:in `call'
  config/initializers/fix_local_cache_middleware.rb:9:in `call'
  lib/gitlab/middleware/static.rb:11:in `call'
  lib/gitlab/webpack/dev_server_middleware.rb:34:in `perform_request'
  lib/gitlab/metrics/requests_rack_middleware.rb:76:in `call'
  lib/gitlab/middleware/release_env.rb:12:in `call'

Following GraphQL query was used;

query groupEpics(
  $groupPath: ID!
  $state: EpicState
  $labelName: [String!]
  $sortBy: EpicSort
  $firstPageSize: Int
  $lastPageSize: Int
  $prevPageCursor: String = ""
  $nextPageCursor: String = ""
) {
  group(fullPath: $groupPath) {
    epics(
      state: $state
      labelName: $labelName
      sort: $sortBy
      first: $firstPageSize
      last: $lastPageSize
      after: $nextPageCursor
      before: $prevPageCursor
    ) {
      nodes {
        id
        iid
        title
        createdAt
        updatedAt
        startDate
        dueDate
        webUrl
        author {
          ...Author
        }
        labels {
          nodes {
            ...Label
          }
        }
        discussions {
          nodes {
            id
          }
        }
      }
      pageInfo {
        ...PageInfo
      }
    }
  }
}

And following variables were provided;

{
  "groupPath": "gitlab-org",
  "state": "opened",
  "lastPageSize": 2,
  "sortBy": "start_date_desc",
  "prevPageCursor": "eyJpZCI6IjIiLCJzdGFydF9kYXRlIjoiMjAyMC0wNC0wMSJ9"
}

Please note that query runs fine if only one of either lastPageSize or sortBy is provided, it fails only when both are provided.