Creates an access token.
Important: Authentication methods differ depending on whether you're building a Wix app or a Wix Headless project.
The endpoint accepts raw HTTP requests. You must pass the request's body
parameters formatted as bytes in the raw HTTP request's body field,
following this template:
{"grant_type": "client_credentials", "client_id": "<APP_ID>", "client_secret": "<APP_SECRET_KEY>", "instance_id": "<INSTANCE_ID>"}.
When the call succeeds, Wix returns {"statusCode": 200} and the created access
token in the body field of the raw HTTP response.
In case the call fails, Wix returns the relevant 4XX error code in the raw
HTTP response's statusCode field and details
about the error in body. Error details follow the
conventions of the Internet Engineering Task Force (IETF).
This method doesn't return any custom errors, but may return standard errors. Learn more about standard Wix errors.