Fix links in English Snap post

See ruby#1888 (comment)

@hsbt, read your GitHub emails! :-p

Author: olivierlacan

en/news/_posts/2018-11-08-snap.md

@@ -9,7 +9,7 @@ lang: en
 
 We released the official snap package of Ruby language.
 
-https://snapcraft.io/ruby
+<https://snapcraft.io/ruby>
 
 Snap is a package system developed by Canonical. It allows you to distribute a software with its dependencies for many different Linux systems. This solves the problem that a user cannot install the latest Ruby release from the default repository of their system like in rpm or apt.
 
@@ -19,7 +19,7 @@ On Ubuntu 16.04 or later, you can use Ruby snap with the following command:
 sudo snap install ruby --classic
 ```
 
-(If you use other Linux distributions, please refer to https://docs.snapcraft.io/installing-snapd/6735)
+(If you use other Linux distributions, please refer to <https://docs.snapcraft.io/installing-snapd/6735>
 
 Our snap uses the "channel" feature to release multiple Ruby series concurrently. For example, without specifying a channel, 2.5.3 will be installed. But if you want to use Ruby 2.4, specify the 2.4 channel like the following:
 
@@ -42,6 +42,6 @@ eval `ruby.env`
 
 Since `$HOME/.gem` is shared by multiple versions, if you switch versions and use them, you will need to recompile C extensions using the `gem pristine --extensions` command.
 
-The initial version of official Ruby snap has released during Snapcraft summit held at Canonical office in London on Nov 6-8th, 2018. Any feedbacks are welcomed at https://github.com/ruby/snap.ruby.
+The initial version of official Ruby snap has released during Snapcraft summit held at Canonical office in London on Nov 6-8th, 2018. Any feedbacks are welcomed at <https://github.com/ruby/snap.ruby>.
 
 Enjoy!