Revert "Migrate to Zola 0.23"

This reverts commit 4f7b33de1f.

templates/shortcodes/client_box.html

@@ -1,4 +1,3 @@
-{% component client_box(href, title, sign, img, img_dark="") %}
 <div class="client_box">
 	<div class="client_box-left">
 		<div class="client_box-left-row">
@@ -22,4 +21,3 @@
 		</p>
 	</div>
 </div>
-{% endcomponent client_box %}