At the moment, an unprocessed entity that has failed to be processed will fail "silently" and the error is sometimes only exposed in the backend logs. This plugin exposes these errors and allows them to be viewed in the frontend. 

This involves adding the following 2 plugins to RHDH

1. Frontend plugin: https://www.npmjs.com/package/@backstage/plugin-catalog-unprocessed-entities
2. Backend plugin: https://www.npmjs.com/package/@backstage/plugin-catalog-backend-module-unprocessed

Investigate the value of this plugin to RHDH and whether or not it provides additional useful information for failed entities than the logs for debugging catalog entity related errors. 

Outcome of the spike will be the creation of a feature to capture onboarding the plugin.