Update registry yaml to latest SSSOM model

[matentzn]

https://github.com/mapping-commons/mh_mapping_initiative/blob/master/registry.yml

Update this to the latest SSSOM spec for mapping registries
request on sssom issue tracker all elements not in the sssom data model

[anitacaron]

Nico updated the registry, and the remaining missing sssom elements are:

• [New metadata element]: registry title sssom#238
• [New metadata element]: registry description sssom#239

[matentzn]

Excellent! Thank you for this!