Create method for failing status checks

In order to show the status check problems, they need to be fetched
from the status api

Co-authored-by: Christian Bruckmayer <cbruckmayer@suse.com>

src/api/app/models/staging/staging_project.rb

@@ -112,6 +112,11 @@ def current_missing_checks
       (relevant_status_reports + relevant_status_reports_for_architectures).map(&:missing_checks).flatten
     end
 
+    def failed_status_checks
+      @failed_status_checks ||= relevant_checks.where(state: Status::Check::FAILED_STATES) +
+                                relevant_checks_for_architectures.where(state: Status::Check::FAILED_STATES)
+    end
+
     private
 
     def cache_problems

src/api/app/models/status/check.rb

@@ -10,6 +10,7 @@ class Status::Check < ApplicationRecord
   validates :state, :name, presence: true
   # TODO: This should be an ENUM
   VALID_STATES = %w[pending error failure success].freeze
+  FAILED_STATES = %w[error failure].freeze
   validates :state, inclusion: {
     in: VALID_STATES,
     message: "State '%{value}' is not a valid. Valid states are: #{VALID_STATES.join(', ')}"
@@ -47,7 +48,7 @@ def success?
   end
 
   def failed?
-    %w[error failure].include?(state)
+    FAILED_STATES.include?(state)
   end
 
   #### Alias of methods