[rubygems/rubygems] Move openssl require to a separate file

So it can be reused.

https://github.com/rubygems/rubygems/commit/b9fc6e40db

lib/rubygems/openssl.rb

@@ -0,0 +1,7 @@
+# frozen_string_literal: true
+
+begin
+  require "openssl"
+rescue LoadError => e
+  raise unless e.path == 'openssl'
+end

lib/rubygems/security.rb

@@ -7,12 +7,7 @@
 
 require 'rubygems/exceptions'
 require 'fileutils'
-
-begin
-  require 'openssl'
-rescue LoadError => e
-  raise unless e.path == 'openssl'
-end
+require_relative 'openssl'
 
 ##
 # = Signing gems