Failing to create new user: Missing JWT signing secret

** (Ash.Error.Unknown) Unknown Error

Context: resolving data on perform Memento.Accounts.User.register_with_password
* Context: resolving data on perform Memento.Accounts.User.register_with_password

** (RuntimeError) Missing JWT signing secret. Please see the documentation for `AshAuthentication.Jwt` for details
  (ash_authentication 3.11.15) lib/ash_authentication/jwt/config.ex:150: AshAuthentication.Jwt.Config.token_signer/2
  (ash_authentication 3.11.15) lib/ash_authentication/jwt.ex:111: AshAuthentication.Jwt.token_for_user/3
  (ash_authentication 3.11.15) lib/ash_authentication/generate_token_change.ex:37: AshAuthentication.GenerateTokenChange.generate_token/3
  (ash_authentication 3.11.15) lib/ash_authentication/generate_token_change.ex:19: anonymous fn/4 in AshAuthentication.GenerateTokenChange.change/3
  (ash 2.15.19) lib/ash/changeset/changeset.ex:2221: anonymous fn/2 in Ash.Changeset.run_after_actions/3