Update file Gemfile

Gemfile

@@ -3,7 +3,7 @@ gem "jekyll", "~> 3.9.3"
 group :jekyll_plugins do
   gem "jekyll-gist", "~> 1.5.0"
   gem "jekyll-coffeescript", "~> 1.1.1"
-  gem "jekyll-assets"
+  gem "jekyll-assets", "~> 1.0.0"
   gem "jekyll-sitemap", "~> 1.4.0"
   gem "jekyll-feed", "~> 0.15.1"
   gem "jekyll-theme-minimal"