Use a unique name for the cloud location of digests artifacts Cardano database

[sfauvel]

Content

Fix the naming of the Cloud storage digests location in the artifacts of the Incremental Cardano DB.
The new format name is: <NETWORK>-e<EPOCH>-i<IMMUTABLE_FILE_NUMBER>.digests.json
Example: mainnet-e5-i456.digests.json"

Pre-submit checklist

• Branch
  • Tests are provided (if possible)
  • Crates versions are updated (if relevant)
  • CHANGELOG file is updated (if relevant)
  • Commit sequence broadly makes sense
  • Key commits have useful messages
• PR
  • No clippy warnings in the CI
  • Self-reviewed the diff
  • Useful pull request description
  • Reviewer requested
• Documentation
  • Update README file (if relevant)
  • Update documentation website (if relevant)
  • Add dev blog post (if relevant)

Issue(s)

Closes #2306

[github-actions]

Test Results

    4 files  ±0     56 suites  ±0   10m 49s ⏱️ -3s
1 598 tests +1  1 598 ✅ +1  0 💤 ±0  0 ❌ ±0 
1 902 runs  +1  1 902 ✅ +1  0 💤 ±0  0 ❌ ±0 

Results for commit 9ca6713. ± Comparison against base commit 2b0ef17.

[jpraynaud]

LGTM 👍