Unsure about why migrating to terraform-plugin-testing break our tests

Could you tell us a little bit more about the difference between what happens in the SDKv2 and what happen in the plugin-testing? I'm not sure about the difference in behaviour and what to watch out for.

I'm trying to migrate here: https://github.com/scaleway/terraform-provider-scaleway/pull/3104

Because of the [sweep redefinition problem](https://developer.hashicorp.com/terraform/plugin/testing/migrating#flag-redefined-panic), I think that I cannot migrate only a part of the code
Therefore I think we are stuck in a complete atomic migration that have to be done in one go.

### terraform-plugin-testing version

```
github.com/hashicorp/terraform-plugin-testing v1.13.2
```

### Relevant provider source code

https://github.com/scaleway/terraform-provider-scaleway/pull/3104/files#diff-17c7c02df009425b1fe3afbb517e9cb2f40510a62d26c1455c6d80a0a57356f9

### Terraform Configuration Files

All the one I had before

### Expected Behavior

The CI should not break as terraform-plugin-testing should be totally retrocompatible with the code I already got. It should not affect the CI in any way to migrate to it.

### Actual Behavior

Many of my jobs are broken. I'm not sure why changing the import path would trigger a fail in my test suite. Is there a change about how the testing it done between sdkv2 and plugin-testing ?

### Steps to Reproduce

### References