violation for `schema:dateModified` being a dateTime (which is de facto standard of cube-creator for a long time now and necessary for high frequency datasets

[Rdataflow]

violation message Violation of DatatypeConstraintComponent: "cube:Cube needs a valid schema:dateModified" with path http://schema.org/dateModified at focus node https://environment.ld.admin.ch/foen/besch_holz_inst_einheit_weniger4/20 (source: _:b88_b709)

steps to reproduce check-metadata with --profile https://cube.link/latest/shape/profile-visualize for any cube-creator output i.e.

 npx barnard59 cube fetch-metadata --cube https://environment.ld.admin.ch/foen/besch_holz_inst_einheit_weniger4/20 --endpoint https://int.lindas.admin.ch/query | npx barnard59 cube check-metadata --profile https://cube.link/latest/shape/profile-visualize | npx barnard59 shacl report-summary

cc @claudiodigallo

[Rdataflow]

@giacomociti I just synced on this with claudio:

• [ ] accept dateTime as well for schema:dateModified