Support OpenAPI 3.2 documents

[martincostello]

Describe the problem to be solved

OpenAPI Specification 3.2.0 was published in September: OpenAPI Specification v3.2.0

However, if attempting to load an OpenAPI 3.2 document into https://redocly.github.io/redoc/ the following error occurs:

Error: Unsupported OpenAPI version: 3.2.0
    at t.detectSpec (https://redocly.github.io/redoc/redoc-demo.bundle.js:2:22498)
    at https://redocly.github.io/redoc/redoc-demo.bundle.js:2:872
    at Generator.next (<anonymous>)
    at https://redocly.github.io/redoc/redoc-demo.bundle.js:2:355
    at new Promise (<anonymous>)
    at r (https://redocly.github.io/redoc/redoc-demo.bundle.js:2:100)
    at b (https://redocly.github.io/redoc/redoc-demo.bundle.js:2:664)
    at https://redocly.github.io/redoc/redoc-demo.bundle.js:2:5064
    at Generator.next (<anonymous>)
    at https://redocly.github.io/redoc/redoc-demo.bundle.js:2:355

Describe the solution you'd like

The ability for redoc to consume OpenAPI 3.2 documents.

Describe alternatives you've considered

None.

Additional context

None.