Replace orderBySectionOrder filter with the built in sort filter

src/index.njk

@@ -7,7 +7,7 @@ eleventyNavigation:
 tags: [ "MainPage" ]
 ---
 
-{% for section in collections.MainPage | IsNotPage(page.url) | IsMainPageSection | orderBySectionOrder %}
+{% for section in collections.MainPage | IsNotPage(page.url) | IsMainPageSection | sort(false, false, "data.sectionOrder") %}
 	{% if not loop.first %}
 		<h2 id="{{ section.data.title | slugify }}">{{ section.data.title }}</h2>
 	{% endif %}