perf: add index on invite dossier_id

db/migrate/20221005090004_add_index_on_dossier_id_to_invites.rb

@@ -0,0 +1,7 @@
+class AddIndexOnDossierIdToInvites < ActiveRecord::Migration[6.1]
+  include Database::MigrationHelpers
+  disable_ddl_transaction!
+  def up
+    add_concurrent_index :invites, [:dossier_id]
+  end
+end

db/schema.rb

@@ -562,6 +562,7 @@ ActiveRecord::Schema.define(version: 2022_10_05_145646) do
     t.text "message"
     t.datetime "updated_at"
     t.integer "user_id"
+    t.index ["dossier_id"], name: "index_invites_on_dossier_id"
     t.index ["email", "dossier_id"], name: "index_invites_on_email_and_dossier_id", unique: true
   end