Response of Password Grant Should be Updated

Description:
In [1], under Invoking the Token API to generate tokens -> Step 2, the response of the token API call with password grant is given as below.

    Response:
    {
        "scope":"default",
        "token_type":"Bearer",
        "expires_in":3600,
        "refresh_token":"ca5a51f18b2edf4eaa9e4b871e42b58a",
        "access_token":"f2c66f146278aaaf6513b585b5b68d1d"
    }

But, the access token from API-M 3.2.0 on-wards are generated in JWT format. Hence, the access_token field of the response should be updated.

Also in API-M 4.1.0, when an application is created, by default only Password and client_credentials grants are selected. Hence, if refresh_token grant type is not selected, the response will not contain the refresh_token field. Better to add that as a note.

[1] https://apim.docs.wso2.com/en/4.1.0/design/api-security/oauth2/grant-types/password-grant/#invoking-the-token-api-to-generate-tokens

Open the linked API-M 4.1.0 Password Grant page and go to “Invoking the Token API to generate tokens,” Step 2. Update the access_token response example to reflect JWT-format tokens and add a note that refresh_token is omitted when the refresh_token grant is not selected.