Remove unused blockname-* classname from sequence-member elements - fixes #3142

wagtail/wagtailadmin/templates/wagtailadmin/block_forms/sequence_member.html

@@ -12,7 +12,7 @@
 
 
 {% endcomment %}
-<li id="{{ prefix }}-container" class="sequence-member blockname-{{ block_type_name }}">
+<li id="{{ prefix }}-container" class="sequence-member">
     <input type="hidden" id="{{ prefix }}-deleted" name="{{ prefix }}-deleted" value="">
     <input type="hidden" id="{{ prefix }}-order" name="{{ prefix }}-order" value="{{ index }}">
     

wagtail/wagtailadmin/tests/test_pages_views.py

@@ -3448,7 +3448,7 @@ class TestInlineStreamField(TestCase, WagtailTestUtils):
         self.assertEqual(response.status_code, 200)
 
         # response should include HTML declarations for streamfield child blocks
-        self.assertContains(response, '<li id="__PREFIX__-container" class="sequence-member blockname-rich_text">')
+        self.assertContains(response, '<li id="__PREFIX__-container" class="sequence-member">')
 
 
 class TestRecentEditsPanel(TestCase, WagtailTestUtils):