Change the `Reference.Type` API with `Reference.TerraformName`

[sergenyalcin]

Description of your changes

This PR changes the Reference.Type API with Reference.TerraformName. This change is necessary to support the multiversion APIs.

The reference configuration API in upjet includes a Type field that identifies the target reference field through the Kubernetes Kind. When you configure a reference field using this Type API, it searches for the target reference resource in the same API version. However, if the specific API version lacks the target reference resource, the reference cannot be resolved. To address this, we will use the TerraformName API for configuring cross-resource references. This API allows the reference resolver to locate the target reference resource across its latest available version.

I have:

• [x] Read and followed Crossplane's contribution process.
• [x] Run make reviewable to ensure this PR is ready for review.
• [ ] Added backport release-x.y labels to auto-backport this PR if necessary.

How has this code been tested

Tested locally.

[sergenyalcin]

/test-examples="examples/cloudplatform/serviceaccount.yaml"