Description of the problem:
If the dynamic-plugins-rhdh configmap is configured to use a non-existent dataIndex URL, deployed workflows disappear from the orchestrator plugin tab, but otherwise no error appears in the UI. 

How reproducible: 100%

Steps to reproduce:

1. Deploy the orchestrator.

2. Deploy some workflows, and execute some.

3. Edit the dataIndex URL in the dynamic-plugins-rhdh CM in the rhdh-operator namespace to point to the wrong URL (for example:

 pluginConfig:
      orchestrator:
        dataIndexService:
          url: http://sonataflow-platform-data-index-service.sonataflow-infra111 

4. Restart the backstage pod.

Actual results: The RHDH pod comes up, but the workflows disappear from the UI. No error is indicated to the user that there is another problem:

Expected results: Error should appear in the UI telling the user that something is wrong.