(FACT-3460) Add puppetlabs specific gem build task

Author: tvpartytonight

Rakefile

@@ -1,6 +1,7 @@
 # frozen_string_literal: true
 
 require 'bundler/gem_tasks'
+require 'open3'
 require 'rspec/core/rake_task'
 require 'facter/version'
 
@@ -13,6 +14,18 @@ task :changelog, [:version] do |_t, args|
   sh "./scripts/generate_changelog.rb #{args[:version]}"
 end
 
+namespace :pl do
+  desc 'build the gem and place it at the directory root'
+  task :gem_build do
+    stdout, stderr, status = Open3.capture3('gem build facter.gemspec')
+    if !status.exitstatus.zero?
+      puts "Error building facter.gemspec \n#{stdout} \n#{stderr}"
+    else
+      puts stdout
+    end
+  end
+end
+
 if Rake.application.top_level_tasks.grep(/^(pl:|package:)/).any?
   begin
     require 'packaging'