chore(deps): update actions/checkout action to v6

[renovate]

This PR contains the following updates:

Package	Type	Update	Change
actions/checkout	action	major	v5 -> v6

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Release Notes

actions/checkout (actions/checkout)

v6

Compare Source

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Slowest examples

Top 10 slowest examples (1.06 seconds, 26.93% of total time)

Example	Description	Time in seconds
spec/unit/recipes/instance_spec.rb:192	test::instance on ubuntu 18.04 is expected to create systemd_unit "memcached_backend_cache.service"	0.22666
spec/unit/recipes/default_spec.rb:116	memcached::default on ubuntu 18.04 is expected to delete file "/etc/sysconfig/memcached"	0.163
spec/unit/recipes/instance_spec.rb:186	test::instance on ubuntu 18.04 is expected to create systemd_unit "memcached_web_cache.service"	0.09643
spec/unit/recipes/instance_spec.rb:78	test::instance on rhel 7 is expected to enable memcached_instance "web_cache"	0.09563
spec/unit/recipes/instance_spec.rb:114	test::instance on ubuntu 18.04 is expected to start memcached_instance "web_cache"	0.09388
spec/unit/recipes/instance_spec.rb:84	test::instance on rhel 7 is expected to create systemd_unit "memcached_web_cache.service"	0.0877
spec/unit/recipes/instance_spec.rb:184	test::instance on ubuntu 18.04 is expected to stop service "disable default memcached"	0.08209
spec/unit/recipes/instance_spec.rb:180	test::instance on ubuntu 18.04 is expected to enable memcached_instance "web_cache"	0.08169
spec/unit/recipes/default_spec.rb:29	memcached::default on rhel 7 is expected not to disable service "disable default memcached"	0.07057
spec/unit/recipes/default_spec.rb:88	memcached::default on rhel 7 is expected to notify "service[memcached]" with action :restart immediately	0.06909