Add health checks for TridentBackendConfig and CI tests for storage class validation

Summary

Currently, Trident storage class units don't have health checks to verify that TridentBackendConfig (TBC) resources reach a Bound state before the unit is considered ready.

Additionally, there are no automated CI tests to validate storage classes and PVC creation.

This ensures that:

The unit waits for TBC to reach Bound phase

The unit waits for TBC status to be Success

The deployment won't proceed if backends fail to initialize

Create CI test for storage class validation

Create a new CI test in units that:

Discovers trident storage classes in the cluster

Tests PVC creation and deletion for trident SC Validates that the storage classes are functional Works across different deployment configurations