Upgrade openapi3-ts package

[Saeger]

The openapi3-ts library is outdated and using an old JSON schema (draft-04).
We should be able to bump the library to the latest and use the latest schema specification along with openapi 3.

[Saeger]

@juliuscc I didn't manage to fix this one! I struggled adapting the new schema to some id field in the json which seems to be required :(

[juliuscc]

If I remember correctly, Openapi and Json Schema still diverge a bit. Could that be the issue?

[Saeger]

Maybe. I will leave this issue open as I didn't found a solution for upgrading it, in case anyone would like to try it.