command "nomad dev example-data" not working

1. The command breaks after some time if the username param is not provided. If it is always needed, it should be declared as a required param, so the cli should raise an error at the moment instead of start processing.
2. Even when we provide a valid username, the command fails with the following error:

Traceback (most recent call last):
  File "<frozen runpy>", line 198, in _run_module_as_main
  File "<frozen runpy>", line 88, in _run_code
  File "/home/judasaca/Documents/nomad-distro-dev/packages/nomad-FAIR/nomad/cli/__main__.py", line 22, in <module>
    run_cli()  # pylint: disable=E1120,E1123
    ^^^^^^^^^
  File "/home/judasaca/Documents/nomad-distro-dev/packages/nomad-FAIR/nomad/cli/cli.py", line 77, in run_cli
    return cli(obj=POPO())  # pylint: disable=E1120,E1123
           ^^^^^^^^^^^^^^^
  File "/home/judasaca/Documents/nomad-distro-dev/.venv/lib/python3.12/site-packages/click/core.py", line 1442, in __call__
    return self.main(*args, **kwargs)
           ^^^^^^^^^^^^^^^^^^^^^^^^^^
  File "/home/judasaca/Documents/nomad-distro-dev/.venv/lib/python3.12/site-packages/click/core.py", line 1363, in main
    rv = self.invoke(ctx)
         ^^^^^^^^^^^^^^^^
  File "/home/judasaca/Documents/nomad-distro-dev/.venv/lib/python3.12/site-packages/click/core.py", line 1830, in invoke
    return _process_result(sub_ctx.command.invoke(sub_ctx))
                           ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
  File "/home/judasaca/Documents/nomad-distro-dev/.venv/lib/python3.12/site-packages/click/core.py", line 1830, in invoke
    return _process_result(sub_ctx.command.invoke(sub_ctx))
                           ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
  File "/home/judasaca/Documents/nomad-distro-dev/.venv/lib/python3.12/site-packages/click/core.py", line 1226, in invoke
    return ctx.invoke(self.callback, **ctx.params)
           ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
  File "/home/judasaca/Documents/nomad-distro-dev/.venv/lib/python3.12/site-packages/click/core.py", line 794, in invoke
    return callback(*args, **kwargs)
           ^^^^^^^^^^^^^^^^^^^^^^^^^
  File "/home/judasaca/Documents/nomad-distro-dev/packages/nomad-FAIR/nomad/cli/dev.py", line 475, in example_data
    main_author = infrastructure.user_management.get_user(username=username)
                  ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
  File "/home/judasaca/Documents/nomad-distro-dev/packages/nomad-FAIR/nomad/infrastructure.py", line 505, in get_user
    user_id = self._admin_client.get_user_id(username)
              ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
  File "/home/judasaca/Documents/nomad-distro-dev/.venv/lib/python3.12/site-packages/keycloak/keycloak_admin.py", line 1272, in get_user_id
    users = self.get_users(query={"username": lower_user_name, "max": 1, "exact": True})
            ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
  File "/home/judasaca/Documents/nomad-distro-dev/.venv/lib/python3.12/site-packages/keycloak/keycloak_admin.py", line 1021, in get_users
    return self.__fetch_paginated(url, query)
           ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
  File "/home/judasaca/Documents/nomad-distro-dev/.venv/lib/python3.12/site-packages/keycloak/keycloak_admin.py", line 236, in __fetch_paginated
    return raise_error_from_response(self.connection.raw_get(url, **query), KeycloakGetError)
                                     ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
  File "/home/judasaca/Documents/nomad-distro-dev/.venv/lib/python3.12/site-packages/keycloak/openid_connection.py", line 421, in raw_get
    self._refresh_if_required()
  File "/home/judasaca/Documents/nomad-distro-dev/.venv/lib/python3.12/site-packages/keycloak/openid_connection.py", line 405, in _refresh_if_required
    self.refresh_token()
  File "/home/judasaca/Documents/nomad-distro-dev/.venv/lib/python3.12/site-packages/keycloak/openid_connection.py", line 386, in refresh_token
    self.get_token()
  File "/home/judasaca/Documents/nomad-distro-dev/.venv/lib/python3.12/site-packages/keycloak/openid_connection.py", line 369, in get_token
    self.token = self.keycloak_openid.token(
                 ^^^^^^^^^^^^^^^^^^^^^^^^^^^
  File "/home/judasaca/Documents/nomad-distro-dev/.venv/lib/python3.12/site-packages/keycloak/keycloak_openid.py", line 375, in token
    return raise_error_from_response(data_raw, KeycloakPostError)
           ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
  File "/home/judasaca/Documents/nomad-distro-dev/.venv/lib/python3.12/site-packages/keycloak/exceptions.py", line 195, in raise_error_from_response
    raise error(
keycloak.exceptions.KeycloakAuthenticationError: 401: b'{"error":"invalid_grant","error_description":"Invalid user credentials"}'