created migration for schemes

db/migrate/20220608142147_create_schemes.rb

@@ -0,0 +1,12 @@
+class CreateSchemes < ActiveRecord::Migration[7.0]
+  def change
+    create_table :schemes do |t|
+      t.string :code null: false
+      t.string :service
+      t.bigint :organisation_id
+      t.datetime :created_at
+
+      t.timestamps
+    end
+  end
+end