Update dependency libv8 to v8

Author: renovate[bot]

external/forkawesome/Gemfile

@@ -3,6 +3,6 @@ source 'https://rubygems.org'
 gem 'jekyll', '3.9.2'
 gem 'safe_yaml', '~> 1.0.4'
 gem 'sass', '~> 3.5'
-gem 'libv8', '~> 3.16.14.19'
+gem 'libv8', '~> 8.4.255.0'
 gem 'therubyracer'
 gem 'fontcustom'

external/forkawesome/Gemfile.lock

@@ -38,7 +38,7 @@ GEM
     json (1.8.6)
     kramdown (2.4.0)
       rexml
-    libv8 (3.16.14.19)
+    libv8 (8.4.255.0)
     liquid (4.0.3)
     listen (3.7.1)
       rb-fsevent (~> 0.10, >= 0.10.3)
@@ -59,8 +59,7 @@ GEM
     sass-listen (4.0.0)
       rb-fsevent (~> 0.9, >= 0.9.4)
       rb-inotify (~> 0.9, >= 0.9.7)
-    therubyracer (0.12.3)
-      libv8 (~> 3.16.14.15)
+    therubyracer (0.11.0)
       ref
     thor (0.20.0)
 
@@ -70,7 +69,7 @@ PLATFORMS
 DEPENDENCIES
   fontcustom
   jekyll (= 3.9.2)
-  libv8 (~> 3.16.14.19)
+  libv8 (~> 8.4.255.0)
   safe_yaml (~> 1.0.4)
   sass (~> 3.5)
   therubyracer