Avoid promoting versioned endpoints

[soxofaan]

I recently noticed in a lot of support requests that users often use full versioned connection URLs like https://openeo.dataspace.copernicus.eu/openeo/1.2 or https://openeo.vito.be/openeo/1.2 instead of the recommended version-less base URLs like openeo.dataspace.copernicus.eu or openeo.vito.be

I found out from a user that they just copy-paste these URLs from https://hub.openeo.org/ where you indeed only see the versioned urls but not the version-less base urls.

Combined with #92, this also means that user will often blindly pick non-production-ready endpoints

[soxofaan]

the openeo hub should at least show the version-less base URL, and do that more prominently (e.g. with a handy copy-paste button) than the versioned endpoint urls