Update Code of Conduct to version 3.0 of the Contributor Covenant

[elichad]

v3.0: https://www.contributor-covenant.org/version/3/0/code_of_conduct/

The ro-crate repo is on version 1.4: https://github.com/ResearchObject/ro-crate/blob/main/CODE_OF_CONDUCT.md

[elichad]

Josh shared the OME CoC which has a different style: https://github.com/ome/governance/tree/main/code-of-conduct