DEV: Upgrade Rails to version 7.1

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Co-authored-by: Jarek Radosz <jradosz@gmail.com>

spec/models/admin_dashboard_data_spec.rb

@@ -42,7 +42,7 @@ RSpec.describe AdminDashboardData do
   end
 
   describe "#problem_message_check" do
-    let(:key) { AdminDashboardData.problem_messages.first }
+    let(:key) { "new_key" }
 
     after { described_class.clear_problem_message(key) }