debezium configuration improvements

[ppanero]

• [ ] datetimes should come in UTC ISO format, currently they come in microseconds, forcing a division in many places of the code (search for 1_000_000).
  • Not possible since the TimestampConverter doesn't work "globally", requires each field to be specified and doesn't support nested fields (i.e. after.created wouldn't work).
• [ ] jsonb columns should be actual dictionaries, no escaped strings.
  • Not possible, unfortunately, unless we write some custom transform Java class...
• [x] Ignore transactions, record_metadata_revision and sipstrore related tables (maybe more)
  • [x] In sandbox ignore files_files for file integrity check

[slint]

Closing, since we managed some of the fixes, but not everything unfortunately...