Allow removing iterations in Issues::Updateservice

We missed a spot earlier when enabling bulk editing of iterations!

ee/app/services/ee/issues/base_service.rb

@@ -74,6 +74,18 @@ module EE
       def epic_param_present?
         params.key?(:epic) || params.key?(:epic_id)
       end
+
+      def filter_iteration
+        return unless params[:sprint_id]
+        return params[:sprint_id] = '' if params[:sprint_id] == IssuableFinder::Params::NONE
+
+        groups = project.group&.self_and_ancestors&.select(:id)
+
+        iteration =
+          ::Iteration.for_projects_and_groups([project.id], groups).find_by_id(params[:sprint_id])
+
+        params[:sprint_id] = '' unless iteration
+      end
     end
   end
 end

ee/app/services/ee/issues/update_service.rb

@@ -8,7 +8,10 @@ module EE
 
       override :filter_params
       def filter_params(issue)
+        params.delete(:sprint_id) unless can_admin_issuable?(issue)
+
         handle_epic(issue)
+        filter_iteration
 
         super
       end

ee/spec/services/ee/issues/update_service_spec.rb

@@ -62,6 +62,22 @@ RSpec.describe Issues::UpdateService do
             end
           end
 
+          context 'setting to IssuableFinder::Params::NONE' do
+            it 'calls NotificationService#removed_iteration_issue' do
+              expect_next_instance_of(NotificationService::Async) do |ns|
+                expect(ns).to receive(:removed_iteration_issue)
+              end
+
+              update_issue(sprint_id: IssuableFinder::Params::NONE)
+            end
+
+            it 'removes the iteration properly' do
+              update_issue(sprint_id: IssuableFinder::Params::NONE)
+
+              expect(issue.reload.iteration).to be_nil
+            end
+          end
+
           context 'setting to another iteration' do
             it 'calls NotificationService#changed_iteration_issue' do
               expect_next_instance_of(NotificationService::Async) do |ns|