Add `relative_url` filter to author profile image

Fixes #125

CHANGELOG.md

@@ -8,6 +8,7 @@ and this project adheres to [Semantic Versioning](http://semver.org/).
 ## [Unreleased] -
 
 ### Fixed
+- Add `relative_url` filter to author profile image. [#125](https://github.com/mmistakes/jekyll-theme-basically-basic/issues/125)
 - Fix rake vulnerability in `.gemspec` file.
 
 ## [1.4.4] - 2019-08-20

_includes/author

@@ -16,8 +16,8 @@
     {% if site.data.authors and site.data.authors[author] %}
       {% assign author_picture = site.data.authors[author].picture %}
     {% endif %}
-    {% unless author_picture contains '://' %}{% assign author_picture = author_picture | relative_url %}{% endunless %}
   {% endif %}
+  {% assign author_picture = author_picture | relative_url %}
 
   {% if author.twitter %}
     {% assign author_twitter = author.twitter %}