feat: convert feature_flags to bigint

db/migrate/20231114111614_change_feature_flags_to_bigint_in_accounts.rb

@@ -0,0 +1,9 @@
+class ChangeFeatureFlagsToBigintInAccounts < ActiveRecord::Migration[7.0]
+  def up
+    change_column :accounts, :feature_flags, :bigint
+  end
+
+  def down
+    change_column :accounts, :feature_flags, :integer
+  end
+end