chore: remove redundant --sync-db step from changelog workflow

[ksylvan]

Fix sync-db CHANGELOG generation flow

Summary

This pull request removes the --sync-db command from the GitHub Actions workflow responsible for updating version numbers and creating tags. The change simplifies the changelog generation step by eliminating an unnecessary database synchronization operation.

(Un)Related Issues 😄

Closes #1920

Reason for Changes

The --sync-db command was redundant and set the metadata incorrectly. Changelog generation typically involves processing recent changes (via --process-prs), and that code was recently changed to update the metadata in the changelog SQLite database.

Impact of Changes

• Performance: The workflow will run faster by skipping the database sync operation, which could shave off a few seconds to minutes depending on the database size and sync complexity.
• Functionality: The changelog generation should still function correctly, as the --process-prs command handles the core logic of updating the changelog based on merged PRs. The changelog.db file is still added to git, ensuring changes are committed.
• Maintenance: Simplifies the workflow, making it easier to maintain and less prone to errors related to database syncing.
• Potential Risks: If the sync was critical for ensuring data consistency (e.g., merging external data sources), this could lead to incomplete or outdated changelog entries. However, based on the diff, it appears the sync was not essential for the primary workflow goal.

Additional Notes

• This change assumes that database synchronization is handled during the --process-pr phase.