Update packages, support 2019-09 and 2020-12 drafts, create new tests, shared cache

[M-casado]

Issue / Ticket reference

NA

Overall changes

• Updated package-lock.json packages to avoid vulnerabilities when installing project.
• Added real support for 2019-09 and 2020-12 JSON Schema drafts, which were not supported before. They were being masked, because Biovalidator was defaulting to the draft-07 when it couldn't get these recent ones.
  • Did this by separating the AJV instances: 2019-09 for "anything other than 2020-12"; and then 2020-12. Reason being AJV docs say draft 2020-12 can't be combined.
  • Modified the tests for the drafts, so specific features/keywords of those drafts are tested.
• Added shared cache for AJV instances, so that API calls are not duplicated.
  • Added tests for this too.
• Added a workflow to run the npm tests automatically in GH, to maintain code quality.

Future TO-DOs

• Investigate whether separating AJV instances in two increases time needed to validate JSON data, reducing performance.