Proposal: Maintain OpenAPI v3.1

[giovanism]

What is the problem?
Missing SSOT of OSB API spec as OpenAPI v3.1 spec.

Who does this affect?
More robust and compliant JSON Schema draft 2020-12 tooling.

Do you have any proposed solutions?
Simply update the openapi.yaml with v3.1, if backward compatibility is required. There are many v3.1 to v3.0 down convert tooling out there to maintain both v3.1 and v3.0. Although there's not a whole lot of update to catch up with so i think manual is preferred.

Additional context
n/a