[Feat]: Migrate Plugin to new backstage frontend system

[ecs-jnguyen]

🔖 Feature description

Please update the harness plugin to be compatible with the new Backstage Frontend System.

🎤 Context

Backstage released a new frontend system for plugins recently.
When I installed the plugin I got this message:

This package's metadata does not indicate feature type information (in exports.backstage nor backstage.features) and may not be compatible with Portal.

Peer dependency is available in Portal at version 18.3.1, which does not satisfy the peer dependency version range. This may result in errors or inconsistent behavior. Please report this issue to the package owner.

react@"^16.13.1 || ^17.0.0"

• https://backstage.io/docs/frontend-system/building-plugins/migrating/

✌️ Possible Implementation