DO NOT MERGE - CI testing for integration branch for CIP-73

[meiersi-da]

@dfordivam and myself found that using the branch-protected integration branch feature-cip-73 is rather difficult, as keeping it up to date requires regular merge commits via PRs. The approach @dfordivam and myself are thus trying out is

• for him to manage the integration branch in the obsidian repo: https://github.com/obsidiansystems/canton-splice/tree/dn/feature-cip-73
  • thus enabling him to use rebasing as needed and when needed without my involvement
• for me to force push his changes to this Draft PR, so that
  • he gets CI results for his integration branch
  • we can use my branch as the PR target for his review requests

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Cluster Testing

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