Missing json-schema drafts

[yordis]

Describe the bug

It seems that spectral doesn't support all the JSON-Schema published drafts

To Reproduce

# .spectral.yaml
rules:
  events-schemas:
    description: Must follow the Events schema
    given: '$'
    then:
      function: schema
      functionOptions:
        schema:
          $ref: ./events.json

// data file: ./events/data/events.json
{
  "$schema": "./events.json", // points to some schema locally
}

{
  "$schema": "https://json-schema.org/draft/2020-12/schema", // this is the issue, it is not recognized by ajv
  "type": "object"
}

Run

spectral lint ./events/data/events.json --ignore-unknown-format

**Expected behavior**
A clear and concise description of what you expected to happen.

```text
$ spectral lint ./events/data/events.json --ignore-unknown-format
Error: no schema with key or ref "https://json-schema.org/draft/2020-12/schema"
    at Ajv.validate (/myapp/spec/node_modules/ajv/lib/ajv.js:93:19)
    at Ajv.validateSchema (/myapp/spec/node_modules/ajv/lib/ajv.js:174:20)
    at Ajv._addSchema (/myapp/spec/node_modules/ajv/lib/ajv.js:307:10)
    at Ajv.compile (/myapp/spec/node_modules/ajv/lib/ajv.js:113:24)
    at WeakMap.get (/myapp/spec/node_modules/@stoplight/spectral/dist/functions/schema.js:70:29)
    at Object.exports.schema (/myapp/spec/node_modules/@stoplight/spectral/dist/functions/schema.js:92:87)
    at Object.exports.lintNode (/myapp/spec/node_modules/@stoplight/spectral/dist/runner/lintNode.js:30:33)
    at runRule (/myapp/spec/node_modules/@stoplight/spectral/dist/runner/runner.js:27:24)
    at Runner.run (/myapp/spec/node_modules/@stoplight/spectral/dist/runner/runner.js:98:17)
    at Spectral.runWithResolved (/myapp/spec/node_modules/@stoplight/spectral/dist/spectral.js:101:22)
No results with a severity of 'error' or higher found!

Environment (remove any that are not applicable):

• "@stoplight/spectral": "^5.9.0"

[P0lip]

Yeah, we do not support newer drafts just yet.
This will be done as a part of our OAS 3.1 support epic, we're about to start soon.
Stay tuned.