adopt `classname` naming in paginate template tag

wagtail/admin/templates/wagtailadmin/chooser/_browse_results.html

@@ -25,4 +25,4 @@
 {% component table %}
 
 {% url 'wagtailadmin_choose_page_child' parent_page.id as pagination_base_url %}
-{% paginate pagination_page base_url=pagination_base_url classnames="navigate-pages" %}
+{% paginate pagination_page base_url=pagination_base_url classname="navigate-pages" %}

wagtail/admin/templates/wagtailadmin/chooser/_search_results.html

@@ -12,5 +12,5 @@
     {% component table %}
 
     {% url 'wagtailadmin_choose_page_search' as pagination_base_url %}
-    {% paginate pages base_url=pagination_base_url classnames="navigate-pages" %}
+    {% paginate pages base_url=pagination_base_url classname="navigate-pages" %}
 {% endif %}

wagtail/admin/templates/wagtailadmin/pages/listing/_pagination.html

@@ -11,7 +11,7 @@ Pagination for page listings. Used by the `{% paginate %}` template tag.
     <ul>
         <li class="prev">
             {% if page.has_previous %}
-                <a data-page="{{ page.previous_page_number }}" href="{{ base_url }}{% pagination_querystring page.previous_page_number page_key=page_key %}" class="{{ classnames }}">
+                <a data-page="{{ page.previous_page_number }}" href="{{ base_url }}{% pagination_querystring page.previous_page_number page_key=page_key %}" class="{{ classname }}">
                     {% icon name="arrow-left" class_name="default" %}
                     {% trans "Previous" %}
                 </a>
@@ -19,7 +19,7 @@ Pagination for page listings. Used by the `{% paginate %}` template tag.
         </li>
         <li class="next">
             {% if page.has_next %}
-                <a data-page="{{ page.next_page_number }}" href="{{ base_url }}{% pagination_querystring page.next_page_number page_key=page_key %}" class="{{ classnames }}">
+                <a data-page="{{ page.next_page_number }}" href="{{ base_url }}{% pagination_querystring page.next_page_number page_key=page_key %}" class="{{ classname }}">
                     {% trans "Next" %}
                     {% icon name="arrow-right" class_name="default" %}
                 </a>

wagtail/admin/templatetags/wagtailadmin_tags.py

@@ -444,7 +444,7 @@ def pagination_querystring(context, page_number, page_key="p"):
 @register.inclusion_tag(
     "wagtailadmin/pages/listing/_pagination.html", takes_context=True
 )
-def paginate(context, page, base_url="", page_key="p", classnames=""):
+def paginate(context, page, base_url="", page_key="p", classname=""):
     """
     Print pagination previous/next links, and the page count. Take the
     following arguments:
@@ -461,13 +461,13 @@ def paginate(context, page, base_url="", page_key="p", classnames=""):
     page_key
         The name of the page variable in the query string. Defaults to 'p'.
 
-    classnames
+    classname
         Extra classes to add to the next/previous links.
     """
     request = context["request"]
     return {
         "base_url": base_url,
-        "classnames": classnames,
+        "classname": classname,
         "request": request,
         "page": page,
         "page_key": page_key,