remove unnecessary codes

src/server/views/admin/customize.html

@@ -1,16 +1,6 @@
 {% extends '../layout/admin.html' %}
 {% block html_title %}{{ customizeService.generateCustomTitle(t('Customize')) }}{% endblock %}
 
-{% block theme_css_block %}
-{% set themeName = getConfig('crowi', 'customize:theme') %}
-
-{% if env === 'development' %}
-<script src="{{ webpack_asset('styles/theme-' + themeName + '.js') }}"></script>
-{% else %}
-<link rel="stylesheet" id="jssDefault" {# append id for theme selector #} href="{{ webpack_asset('styles/theme-' + themeName + '.css') }}" />
-{% endif %}
-{% endblock %}
-
 {% block html_additional_headers %}
 {% parent %}
 <!-- CodeMirror -->