aws-exports.js values not generated when using override.ts

### How did you install the Amplify CLI?

npm

### If applicable, what version of Node.js are you using?

v16.20.2

### Amplify CLI Version

12.12.6

### What operating system are you using?

macOS

### Did you make any manual changes to the cloud resources managed by Amplify? Please describe the changes made.

N/A

### Describe the bug

When setting OAuth values in `amplify/backend/auth//override.ts`, for example:

```
...
resources.userPoolClient.allowedOAuthFlows = ["code"];
resources.userPoolClient.allowedOAuthScopes = ["openid", "email", "profile"];
...
```

These values are not added to the `aws-exports.js` file.

If the values are added to `cli-inputs.json`, for example:

```
"oAuthMetadata": "{\"AllowedOAuthFlows\":[\"code\"],\"AllowedOAuthScopes\":[\"email\",\"openid\",\"profile\"],
```

The values do appear in `aws-exports.js`:

```
"oauth": {
...
"scope": [
"email",
"openid",
"profile"
],
"responseType": "code"
...
},
```

My understanding is these should be equivalent and `override.ts` is the more modern way of adding these settings.

### Expected behavior

aws-exports.js contains OAuth values when set from `override.ts` file

### Reproduction steps

1. Use `amplify/backend/auth//override.ts` to add OAuth properties
a. e.g.
```
resources.userPoolClient.allowedOAuthFlows = ["code"];
resources.userPoolClient.allowedOAuthScopes = ["openid", "email", "profile"];
```
2. Perform an `amplify push`
3. Notice `aws-exports.js` does not update

### Project Identifier

_No response_

### Log output

_No response_

### Additional information

I may be misunderstanding this, and if using `override.ts`, there's another way of acccessing the values that are set, instead of using `aws-exports.js`, but I'm not sure what this process is if it exists.

Thanks!

### Before submitting, please confirm:

- [X] I have done my best to include a minimal, self-contained set of instructions for consistently reproducing the issue.
- [X] I have removed any sensitive information from my code snippets and submission.

Start with amplify/backend/auth//override.ts and compare how its OAuth values are handled with the cli-inputs.json path during amplify push. Inspect the generated aws-exports.js and verify whether allowedOAuthFlows and allowedOAuthScopes are carried through. Done means the documented override.ts reproduction produces the expected oauth responseType and scope values.

Written by the indexing model from the issue text.