Backend work needed for feature specs on issues list to pass

Working through switching the issue lists view over to Vue/GraphQL, and @cngo found a few things that we need backend assistance on in order to get tests passing (need to run these specs off of MR !61123 (closed)):

• spec/features/groups/issues_spec.rb:86 - we truncate counts on the haml page. the vue page uses graphql though which doesn't truncate - need backend to truncate counts for the graphql query too?
• spec/features/user_sorts_things_spec.rb:23 and :36 - the haml page persists sort across list views. the sort is saved in SortingPreference#set_sort_order i think. need to work with backend to figure out best way to implement this persistence with the GraphQL issues list
• spec/features/projects/labels/issues_sorted_by_priority_spec.rb:18 and :48 - sorting issues by label priority in graphql seems to be different than in haml - get backend to check difference?
• spec/features/issuables/issuable_list_spec.rb - sorts labels alphabetically - test passes locally but fails on ci (shows a,B,X,z on ci screenshot, locally is B,X,a,z). not sure why it would differ on ci - backend can have a look?
• spec/features/issues/csv_spec.rb:87 !76524 (merged) - get backend to see if more complex query is okay. refactor adds sort=created_date&state=opened to request
• spec/features/issues/user_sorts_issues_spec.rb:27, :128-:190 - 1) need to persist sort option with backend help 2) there are tests for due_date params because the calendar uses due_date. it's not documented that we can filter the issues list by due_date - maybe backend can move these tests to where we test the calendar?
• spec/features/issues/filtered_search/dropdown_base_spec.rb:20 - slow_requests doesn't seem to slow down graphql queries hence the failure? need backend to check if this is the reason it's failing

Related to #323743 (closed).