Static web app using Azure AD B2c for sign in does not work

I edited this project to enable aad b2c as my auth provider: [Static Web Template](https://github.com/MicrosoftDocs/mslearn-staticwebapp-authentication)

**Expected behavior**
When going to https://gentle-flower-02ac39b0f.1.azurestaticapps.net/.auth/login/aab2c, I'm expecting to get the aadb2c login/create user screen, but instead I'm getting a 404

aad, twitter, and github logins are working as auth methods

I followed this article: https://docs.microsoft.com/en-us/azure/active-directory-b2c/configure-authentication-in-azure-static-app.

**Additional context**
This is the user configured user flow in AAD B2C: [Login user flow](https://lettrlabs.b2clogin.com/lettrlabs.onmicrosoft.com/oauth2/v2.0/authorize?p=B2C_1_signup-signing&client_id=fd887dd0-3b7d-42f3-9c2a-b4dabce22e56&nonce=defaultNonce&redirect_uri=https%3A%2F%2Fgentle-flower-02ac39b0f.1.azurestaticapps.net%2F.auth%2Flogin%2Faadb2c%2Fcallback.&scope=openid&response_type=code&prompt=login)
Source code: [my-static-web-app-authn-main.zip](https://github.com/Azure/static-web-apps/files/9374103/my-static-web-app-authn-main.zip)
Likely related to [This issue](https://github.com/Azure/static-web-apps/issues/884)

I have the client_id/secret configured in the app