fix: missing list_latest_versions due to loose regex on gem files

[YOU54F]

Fixes an issue introduced in #168.

Raised on slack https://pact-foundation.slack.com/archives/C9VHVEDE1/p1724228717621349

<internal:/usr/local/lib/site_ruby/3.3.0/rubygems/core_ext/kernel_require.rb>:136:in `require': cannot load such file -- pact_broker/client/pacts/list_latest_versions (LoadError)
        from <internal:/usr/local/lib/site_ruby/3.3.0/rubygems/core_ext/kernel_require.rb>:136:in `require'
        from /usr/lib/ruby/gems/3.3.0/gems/pact_broker-client-1.76.0/lib/pact_broker/client/cli/pact_commands.rb:44:in `list_latest_pact_versions'
        from /usr/lib/ruby/gems/3.3.0/gems/thor-1.3.1/lib/thor/command.rb:28:in `run'
        from /usr/lib/ruby/gems/3.3.0/gems/thor-1.3.1/lib/thor/invocation.rb:127:in `invoke_command'
        from /usr/lib/ruby/gems/3.3.0/gems/thor-1.3.1/lib/thor.rb:527:in `dispatch'
        from /usr/lib/ruby/gems/3.3.0/gems/thor-1.3.1/lib/thor/base.rb:584:in `start'
        from /usr/lib/ruby/gems/3.3.0/gems/pact_broker-client-1.76.0/lib/pact_broker/client/cli/custom_thor.rb:34:in `start'
        from /usr/lib/ruby/gems/3.3.0/gems/pact_broker-client-1.76.0/bin/pact-broker:10:in `<top (required)>'
        from /usr/bin/pact-broker:25:in `load'
        from /usr/bin/pact-broker:25:in `<main>'

whereby we are excluding files from being included in the gem, however we were looking for any path+filename that includes test which captures lib/pact_broker/client/pacts/list_latest_versions.rb

This change updates the rejection list to only include spec/, test/, .github/.

It also removesfeatures (not sure why I included that before for exclusion)