Configure credentials in within specific folders

### What feature do you want to see added?

Please can we allow credentials to be configured within folders, e.g:
```
- string:
description: "Test Cred"
id: "example"
scope: GLOBAL
secret: "infra-scope-test"
folder: "example-folder"
```

Rational: We want to create credentials in code that are not accessible to all folders. Currently this is a security issue and allow any credentials created to be accessed by any folder and any build.

### Upstream changes

_No response_