Follow-up from "Require Product Intelligence reviews for frontend Snowplow events"

The following discussion from !54273 (merged) should be addressed:

Non-blocking idea I had one idea how to make future pattern additions easier and more obvious and came up with the following structure:

ANY_CHANGE = Object.new

FILE_CHANGES = {
  tracking: {
    'lib/gitlab/tracking.rb' => ANY_CHANGE
    'spec/lib/gitlab/tracking_spec.rb' => ANY_CHANGE,
    'app/helpers/tracking_helper.rb' => ANY_CHANGE,
    'spec/helpers/tracking_helper_spec.rb' => ANY_CHANGE,
    'app/assets/javascripts/tracking.js' => ANY_CHANGE,
    'spec/frontend/tracking_spec.js' => ANY_CHANGE,
    'generator_templates/usage_metric_definition/metric_definition.yml' => ANY_CHANGE,
    'lib/generators/rails/usage_metric_definition_generator.rb' => ANY_CHANGE,
    'spec/lib/generators/usage_metric_definition_generator_spec.rb' => ANY_CHANGE,
    'config/metrics/schema.json' => ANY_CHANGE
  }
  usage_data: {
    /usage_data/ => ANY_CHANGE,
  }
  metrics: {
    %r{config/metrics/.*\.yml} => ANY_CHANGE,
  },
  metrics_dictionary: {
    'doc/development/usage_ping/dictionary.md' => ANY_CHANGE,
  },
  snowplow: {
    /\.rb$/ => /Gitlab::Tracking\.event/,
    /\.(js|vue)$/ => Regexp.union(
      'Tracking.event',
      /\btrack\./,
      'data-track-event'
    ),
    /\.haml$/ => %r{\b(event|track)\b}
  },
}

changed_files = determine_changed_files(all_changed_files)
# returns a Hash: <section> => [<file>, ...]
# Example: { tracking: ['lib/gitlab/tracking.rb', ...], metrics: [ ... ] }

changed_files then could be used below like:

matching_changed_files = changed_files.flatten(1)

if matching_changed_files.any?
  mention = if helper.draft_mr?
              "`#{ENGINEERS_GROUP}`"
            else
              ENGINEERS_GROUP
            end

  warn format(CHANGED_FILES_MESSAGE, changed_files: helper.markdown_list(matching_changed_files), engineers_group: mention)
  warn format(UPDATE_METRICS_DEFINITIONS_MESSAGE) if changed_files.key?(:metrics)

  fail format(UPDATE_DICTIONARY_MESSAGE) if changed_files.key?(:metrics) && changed_files.key?(:metrics_dictionary)

  labels = ['product intelligence']
  labels << 'product intelligence::review pending' unless helper.mr_has_labels?('product intelligence::approved')

  markdown(helper.prepare_labels_for_mr(labels))
end

WDYT of this approach? Would this make adding patterns in the future easier? 🤔

Again, not this MR and just an idea but happy to collaborate on this if you like this idea!