### Description

The current length limit for the `login` parameter in an HTTP connection is 500 characters. It'd be nice if this was 5000 characters like the `password` parameter.

### Use case/motivation

We've run into an issue with an API we need to integrate with. It uses basic HTTP authentication, and both username and password are about 900 characters long each. We don't have any control over this API, so we cannot change the authentication method, nor the length of these usernames and passwords.

### Related issues

_No response_

### Are you willing to submit a PR?

- [X] Yes I am willing to submit a PR!

### Code of Conduct

- [X] I agree to follow this project's [Code of Conduct](https://github.com/apache/airflow/blob/main/CODE_OF_CONDUCT.md)

"""Initialize Airflow database."""
    import_all_models()
    db_exists = _get_current_revision(session)
    if db_exists:
        upgradedb(session=session)
    else:
        _create_db_from_orm(session=session)
    if conf.getboolean("database", "LOAD_DEFAULT_CONNECTIONS") and load_connections:
        create_default_connections(session=session)
    
    add_default_pool_if_not_exists(session=session)
    synchronize_log_template(session=session)
def _get_alembic_config():
    from alembic.config import Config
    package_dir = os.path.dirname(airflow.__file__)
    directory = os.path.join(package_dir, "migrations")
    alembic_file = conf.get("database", "alembic_ini_file_path")
    if os.path.isabs(alembic_file):
        config = Config(alembic_file)
    else:
        config = Config(os.path.join(package_dir, alembic_file))
    config.set_main_option("script_location", directory.replace("%", "%%"))
    config.set_main_option("sqlalchemy.url", settings.SQL_ALCHEMY_CONN.replace("%", "%%"))
    return config
def _get_script_object(config=None) -> ScriptDirectory:
    from alembic.script import ScriptDirectory
    if not config:
        config = _get_alembic_config()
    return ScriptDirectory.from_config(config)
def _get_current_revision(session):