Custom provider error after update to v4

[nunorbatista]

Description 🐜

I had an issue in the past with our custom OAuth implementation that I recorded in this issue.
I managed to overcome the issue by passing the parameter useAuthTokenHeader: false to the provider. Everything was fine until I tested the update to the V4.

Is this a bug in your own project?

Yes

How to reproduce ☕️

Now, I get:

[next-auth][error][OAUTH_CALLBACK_ERROR] 
https://next-auth.js.org/errors#oauth_callback_error invalid_request {
  error: {
    message: 'invalid_request',
    stack: 'OPError: invalid_request\n' +

To overcome this, I tried to do a custom implementation of the Token param, like this:

      token: {
        url: process.env.ISRICO_URL + '/APIIntegration/Token',
        async request(context) {
         
          const tokens = await makeTokenRequest(context)
          /* this function returns:
            const tokens = {
              "access_token": <TOKEN>,
              "refresh_token": <REFRESH_TOKEN>
              "token_type": "bearer",
              "expires_in": 3600,
              "scope": ""
          }
           */
          return { tokens }
        }
      },

But I still have the same error. Do you have an idea on what changed for NextAuth to ignore the useAuthTokenHeader setting?

Screenshots / Logs 📽

No response

Environment 🖥

System:
OS: Windows 10 10.0.18363
CPU: (8) x64 Intel(R) Core(TM) i7-8665U CPU @ 1.90GHz
Binaries:
Node: 14.18.1 -
Yarn: 1.22.4 -
npm: 8.0.0 -
Browsers:
Chrome: 96.0.4664.45
Edge: Spartan (44.18362.1593.0)
Internet Explorer: 11.0.18362.1766
npmPackages:
next: 12.0.4 => 12.0.4
next-auth: ^4.0.1 => 4.0.1
react: 17.0.2 => 17.0.2

Contributing 🙌🏽

Yes, I am willing to help solve this bug in a PR