i-numbers can have a dotted suffix

[paul-butcher]

What does this change?

See wellcomecollection/wellcomecollection.org#10565

There are some iconographic numbers (e.g. 3329263i.104 on vu3mwczx) which have a numeric suffix after a dot. These are currently being erroneously ignored by the validation that expects a number followed by i.

This fixes that bug.

How to test

This is pretty well isolated, so the unit tests should cover it quite well. When this has been deployed and the relevant records indexed, then records like vu3mwczx should show a Reference beneath the title (Reference: 3329263i.104 in this case), in the same way as https://wellcomecollection.org/works/g8j7y2xh

Have we considered potential risks?

It is syntactically possible that a Sierra record might have multiple valid 001 fields. If a dotted one appears ahead of an undotted one, then the reference displayed for that record will change.

1. I don't think that is likely
2. If it does happen, it will probably be more correct
3. I think this number is only for display, and no machines are relying on it to preferentially point to a dotless i-number

[rcantin-w]

I approve of the new regex, I've tested our known scenarios with a regex testing tool and it works nicely, but I can't approve the rest of the scala code 😬 so assigning others as reviewers.

https://regex101.com/