`site.related_posts` should return an array of latest posts when no related ones are found due to `lsi` being disabled (GitHub Page's doesn't support it).
This works around that bug by showing the 4 latest posts to populate the "You May Also Enjoy" module when enabled with `related: true`.
Fixes#554
Related: #978#1022
This removes a buggy conditional that checks if `related_label` is
available in translations before displaying the header for related
posts but this header already handle missing translation by using a
default string.
With this fix the header is displayed even if the translation for this
label isn't available.
Fix#900
Liquid Warning: Liquid syntax error (line 3): Expected dotdot but found id in "(page.header.overlay_color or page.header.overlay_image) or page.header.image" in /_layouts/single.html
Liquid Warning: Liquid syntax error (line 1): Expected dotdot but found id in "(page.header.overlay_color or page.header.overlay_image) or page.header.image" in /_layouts/archive.html
Liquid Warning: Liquid syntax error (line 3): Expected dotdot but found id in "(page.header.overlay_color or page.header.overlay_image) or page.header.image" in /_layouts/splash.html