Implement process for keeping track of localized page drift

[paigecalvert]

The Helm docs have several different locales. However, we do not have a formalized process for keeping track of "drift" in the localized content. We should have a process that allows contributors to easily identify when there are material changes to the English language docs that are not yet reflected in the localized versions of the given page(s).

The OpenTelemetry docs have a good process for this that we can replicate in the Helm docs. See https://opentelemetry.io/docs/contributing/localization/#track-changes

Here's an overview of the process:

• They use a default_lang_commit front-matter field in localized docs to track the specific commit in the English language version of the give page that the translation was based off. This helps contributors quickly determine which newer commits in the English language page might need to be added to the localized version
• They use an npm run check i18n command to check which localized versions of an English language page need to be updated: https://www.npmjs.com/package/@lingual/i18n-check?activeTab=readme . This is useful to run after making a material change a page in the main English locale to understand what other locales are impacted

This issue proposes exploring and implementing these processes for the Helm docs.

[Andygol]

RE #1929