Audit Job classes - group them in Audit module namespace

[ndushay]

from storytime 2022-11-21

Audit job classes should all be in the "Audit" namespace. This includes

• CatalogToMoabJob
• ChecksumValidationJob
• MoabToCatalogJob
• Not sure about ValidateMoab -- it is possibly only run by preservation-robots as a check before ingest into prescat ... @justinlittman is working on understanding whether it is sometimes run as part of other three audits above - maybe ask him? -- NO. See PR add comments about use of ValidateMoabJob #2164

ALSO you should do a similar refactor into namespaces for service classes (@justinlittman do you agree)

• checksum_validator --> should this be in audit namespace (Yes - it's already done.)
• audit_results_reporter ... should this be in audit namespace (Possibly?)

having job names match queue names is ticketed separately as #2056

There is a separate ticket for CatalogToArchiveJob: #2059

note that the analogous replication audit refactoring is a separate ticket, #2059

analogous ticket for replication jobs is #2063

[ndushay]

NOTE: wait for sidekiq to replace redis (#1984) in production before this change is merged to prod!