Set Up Okta Identity Provider in an Amazon Cognito User Pool

# 💡 Summary #

Our project aims to integrate Okta as an OpenID Connect (OIDC) identity provider (IdP) within an Amazon Cognito user pool. This integration will allow users in our Okta app to obtain user pool tokens from Amazon Cognito.

## Motivation and context ##

Allows for .gov cross-service account management.

## Implementation notes ##

- Set up a user pool with the necessary configurations.
- Ensure that the standard attribute “email” is selected during creation.
- Create an app client within the user pool to enable the hosted web UI.
- Okta: Select OpenID Connect and Web Application.
- Configure the app settings, including the Sign-in redirect URIs
- Add Okta as an OIDC IdP in Your User Pool:
- Map SAML Attributes to User Pool Attributes

## Acceptance criteria ##

- [ ] Configure testing in Staging envirionment
- [ ] Update Playwright test if necessary
- [ ] Deploy production on successful test