Removed traces of grey risk card (EXPOSUREAPP-3051) (#1699)

* Removed traces of grey risk card.

* Removed UNKNOWN_RISK_INITIAL constant.

* Removed unused method.

* Removed old comments.

* Introduce risklevel calculation failure state to get consistent card states.

* Cleaned up the risk card states.
Refactored "RiskLevel" to be calculated based on either result or failure reasons.
Added the new "no internet" error card.

* Updated color states.

* Fixed card color issues.

* Fixed detekt issues.

* Remove test for deleted file.

* Fix test regressions.

* Fixed tests and LINTs.

Co-authored-by: harambasicluka <64483219+harambasicluka@users.noreply.github.com>
Co-authored-by: Matthias Urhahn <matthias.urhahn@sap.com>