JWT Authorization Grant flow

[Rishabh-2534]

Section 2.1. Using JWTs as Authorization Grants of RFC 7523 JSON Web Token (JWT) Profile for OAuth 2.0 Client Authentication and Authorization Grants defines another flow for access token issuance which is different from OAuth 2.0 standard flows defined in RFC 6749. We call it JWT Authorization Grant flow.
In the flow, a JWT (RFC 7519) is used as an authorization grant, which indicates that its holder has been authorized to get an access token. The JWT as an authorization grant is the same concept as an authorization code in the authorization code flow (RFC 6749 Section 4.1).

[panva]

https://github.com/panva/node-oidc-provider/blob/v9.5.2/docs/README.md#custom-grant-types