Update Gemfile to reflect a modern Puppet #156

Job	Run time
Static code analysis (7.22.0, 2.7.7)	1m 49s
Static code analysis (7.22.0, 3.0.5)	1m 17s
Integration tests (puppet7, ubuntu-18.04)	3m 4s
Integration tests (puppet7, ubuntu-20.04)	2m 44s
Static code analysis (7.22.0, 3.1.3)	1m 35s
Integration tests (puppet7, ubuntu-22.04)	2m 39s
Integration tests (puppet7, centos-7)	5m 34s
Integration tests (puppet7, centos-9)	4m 26s
Integration tests (puppet7, debian-10)	2m 37s
Integration tests (puppet7, debian-11)	2m 32s
Integration tests (puppet8, ubuntu-18.04)	2m 57s
Integration tests (puppet8, ubuntu-20.04)	3m 2s
Integration tests (puppet8, ubuntu-22.04)	2m 38s
Integration tests (puppet8, centos-7)	4m 31s
Integration tests (puppet8, centos-9)	4m 56s
Integration tests (puppet8, debian-10)	2m 55s
Integration tests (puppet8, debian-11)	2m 53s
	52m 9s

Provide feedback