Can't make this example work on HTTPS

### This issue is for a: bug report
```
- [x] bug report -> please search issues before submitting
- [ ] feature request
- [ ] documentation issue or request
- [ ] regression (a behavior that used to work and stopped in a new release)
```

### Minimal steps to reproduce
>

This example works well on localhost, but on production, when application is running on GCP, trying to connect to Azure, and redirect always triggers back not POST but GET endpoint.

I see in the logs that request is correct, looks like this:

```
https://login.microsoftonline.com/SOME_UUID/oauth2/v2.0/authorize?
client_id=clientId
scope=openid%20profile%20offline_access&
redirect_uri=https%3A%2F%2Fcrystal-acc.bol.io%2Fapi%2Fauth%2Fazure%2Fsignin&
client-request-id=YYY&
response_mode=form_post&
response_type=code&
x-client-SKU=msal.js.node&
x-client-VER=2.16.0&
x-client-OS=linux&
x-client-CPU=x64&
client_info=1&
code_challenge=SOME1&
code_challenge_method=S256&
state=MY_STATE
```

Even if I specify `res.redirect(308, authCodeUrlResponse);` it gives no effect.

What kind of configuration is in Azure to not do this VERB conversion?

### Any log messages given by the failure
>

### Expected/desired behavior
>

### OS and Version?
Linux, Kubernetes, GCP

### Versions
>

### Mention any other details that might be useful

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