Dashboard is implicitly validating against v1.1

[ml-evs]

This is fine for now, as v1.1 only made minor changes that do not break validation, but we should consider for future versions what the dashboard should actually show. It may be that the validator should start selecting the appropriate version that the implementation reports, though this would require a series of changes in optimade-python-tools.

cc @CasperWA

[CasperWA]

Maybe we only focus on v1? But.. well, one might want to know all the various versions supported by an implementation? Although, I as implementer will only ever keep one supported version - unless some drastic change occurs (read: a major version change).

[rartino]

Note the question in: Materials-Consortia/OPTIMADE#366 (comment)

If our interpretation of semantic versioning means that an implementation that validates in v1.x always must validate in v1.y, y>x, then indeed the validator only needs to validate the latest v1.