Bring app in line with Hanami 2.1.0 base

app/relations/trips.rb

@@ -0,0 +1,20 @@
+# frozen_string_literal: true
+
+module Adamantium
+  module Relations
+    class Trips < ROM::Relation[:sql]
+      schema :trips, infer: true do
+        associations do
+          has_many :post_trips
+          has_many :posts, through: :post_trips
+        end
+      end
+
+      auto_struct(true)
+
+      def published
+        where(self[:start_date] <= Time.now)
+      end
+    end
+  end
+end