update uri

[jburel]

Point uri to ome_model_doc https://ome-model.readthedocs.io/en/stable/

[sbesson]

Do you foresee the need to override this base URI ever in the near future? Otherwise, an alternative would be to completely get rid of this variable and its usage in https://github.com/ome/bio-formats-documentation/blob/ab5e213dbf1b5ef9e864ecc2e3a99bc67d83e67c/sphinx/conf.py#L217-L218 and update https://github.com/ome/bio-formats-documentation/blob/ab5e213dbf1b5ef9e864ecc2e3a99bc67d83e67c/sphinx/conf.py#L170 to use the new base URI

[jburel]

I think the BF linkcheck job could use latest (merge PR) instead of stable (release/tag). That will be closer to what was there before I have no strong opinion

[jburel]

Discussed during the weekly BF call, we decided not to keep the variable

[sbesson]

Probably fixes https://github.com/ome/bio-formats-documentation/issues/14 (as no longer applicable) too