Make assignee field a user autocompleter

spec/support/edit_fields/edit_field.rb

@@ -50,6 +50,7 @@ class EditField
   def expect_state_text(text)
     expect(context).to have_selector(@selector, text:)
   end
+
   alias :expect_text :expect_state_text
 
   def expect_value(value)
@@ -76,6 +77,7 @@ class EditField
       end
     end
   end
+
   alias :activate_edition :activate!
 
   def openSelectField
@@ -93,6 +95,7 @@ class EditField
   def active?
     @context.has_selector? "#{@selector} #{input_selector}", wait: 1
   end
+
   alias :editing? :active?
 
   def expect_active!
@@ -242,8 +245,9 @@ class EditField
     when 'version'
       'version-autocompleter'
     when 'assignee',
-           'responsible',
-           'priority',
+        'responsible'
+      'op-user-autocompleter'
+    when 'priority',
         'status',
         'type',
         'category',