Extend v3.Cluster coverage in E2E

[salasberryfin]

Description

When the support for importing CAPI clusters based on management.cattle.io resources was first introduced in #362, a single E2E test suite was added for this alternative controller (based on the existing import-gitops suite).

As we ultimately move to v3.Cluster we need to extend the E2E coverage. The initial approach could be to migrate the existing suites to focus on management.cattle.io cluster resources rather than provisioning.cattle.io. Doing so, we guarantee that we can support these scenarios with the new controller and importing mechanism.

This will mean that we need to cover (at least):

• GitOps approach via Fleet.
• Validate that we do not break v2prov.
• Update labels.
• Deploying Rancher with embedded-cluster-api feature disabled.

[salasberryfin]

Following on the work done in #519, the E2E tests for the v3 controller must cover also CAPRKE2.