CentOS8: Gem install is failing because pathspec 1.0.0 requires ruby 2.6

The puppet-openstack-litmus-7.10-centos-8-stream job is failing because of the following error.

https://zuul.opendev.org/t/openstack/build/cb062498280c41599ea5fdc4fa62c3c4
~~~
Gem::RuntimeRequirementNotMetError: pathspec requires Ruby version >= 2.6.0. The
current ruby version is 2.5.0.
An error occurred while installing pathspec (1.0.0), and Bundler cannot
continue.
Make sure that `gem install pathspec -v '1.0.0' --source
'https://rubygems.org/'` succeeds before bundling.

In Gemfile:
  puppet-openstack_spec_helper was resolved to 18.0.0, which depends on
    puppet_litmus was resolved to 0.32.0, which depends on
      puppet-modulebuilder was resolved to 0.3.0, which depends on
        pathspec
bundler: failed to load command: rake (/home/zuul/workspace/.bundled_gems/bin/rake)
/usr/local/share/gems/gems/bundler-2.2.11/lib/bundler/resolver.rb:63:in `rescue in start': Bundler could not find compatible versions for gem "puppetlabs_spec_helper": (Bundler::VersionConflict)
  In Gemfile:
    puppet-openstack_spec_helper was resolved to 18.0.0, which depends on
      puppetlabs_spec_helper
~~~