Add tabbed changeform support (#211).

* WIP : basic templates

* Add params

* Working override

* Use headerless version only during tabs

* Move CSS to separate file

* Extract js to static folder

* script is not self-closing

* [pre-commit.ci] auto fixes from pre-commit.com hooks

for more information, see https://pre-commit.ci

* use classList for updating classes

* Add EOF (newline) to new text files

* a simple test to keep up code coverage

* [pre-commit.ci] auto fixes from pre-commit.com hooks

for more information, see https://pre-commit.ci

* Fieldsets are not tabbed by default

* rename templatetag

* use default page if show_*_tabs are false

* Narrow down css to admin-interface

* Fix typo

* keep codacy happy

* prefix tab classes with tabbed-changeform-

* horizontal scrolling

* Update colors

* color updates

* add back missing font bold

Co-authored-by: vaz <vmohan@lenbox.io>
Co-authored-by: pre-commit-ci[bot] <66853113+pre-commit-ci[bot]@users.noreply.github.com>

admin_interface/templates/admin/base_site.html

@@ -114,7 +114,8 @@
           href="{% static 'admin_interface/css/import-export.css' %}?v={{ version_md5_cache }}"/>
     <link rel="stylesheet" type="text/css"
           href="{% static 'admin_interface/css/rtl.css' %}?v={{ version_md5_cache }}"/>
-
+    <link rel="stylesheet" type="text/css"
+          href="{% static 'admin_interface/css/tabbed-changeform.css' %}?v={{ version_md5_cache }}">
 
 {% if current_lang == 'fa' %}
 <link rel="stylesheet" type="text/css" href="https://cdn.jsdelivr.net/gh/rastikerdar/vazir-font@v27.2.2/dist/font-face.css" />