Add source URLs to the four database names in dcterms:description

[turbomam]

The ontology header dcterms:description (in src/ontology/metpo-edit.owl and src/ontology/metpo-odk.yaml) names the four harmonized trait databases without links: BacDive, BactoTraits, Madin bacteria_archaea_traits, MetaTraits. They read like bare identifiers and are not traceable.

The EBI OLS submission (EBISPOT/ols4#1294) now gives each its authoritative source URL, which are the same IAO:0000119 provenance values already used on the synonyms in metpo.owl:

• BacDive: https://bacdive.dsmz.de/
• BactoTraits: https://ordar.otelo.univ-lorraine.fr/files/ORDAR-53/BactoTraits_databaseV2_Jun2022.csv
• Madin et al.: https://github.com/jmadin/bacteria_archaea_traits
• MetaTraits: https://metatraits.embl.de/

Align the OWL description to the same traceable form, then rebuild and cut a release so it propagates to BioPortal and OLS.