add local-env with mixed dbsync/dolos data source nodes and diff returned values

[kpinter-iohk]

Description

This PR adds:

• A new debug data source dolos-diff that runs data source queries against both dbsync and dolos, and logs if the result is not identical, then returns the result from dolos.
• New deployment -d 8 to local-env to deploy an env with 2 nodes that use db-sync and 3 that use the above dolos/db-sync diff source.
• This testing revealed that McHashDataSource::get_candidates returns slightly different results, stake_delegation being off. I added a comment in the code where this is happening.

Checklist

• Commit sequence broadly makes sense and commits have useful messages.
• The size limit of 400 LOC isn't needlessly exceeded
• The PR refers to a JIRA ticket (if one exists)
• New tests are added if needed and existing tests are updated.
• New code is documented and existing documentation is updated.
• Relevant logging and metrics added
• Any changes are noted in the changelog.md for affected crate
• Self-reviewed the diff