Function payment_provider_test_connection 

pub fn payment_provider_test_connection(
    root: &mut Value,
    app_root: &Path,
    runtime_conf_path: Option<&Path>,
    owner_route_value: &str,
    provider: &str,
    actor_user_id: i64,
    request: PaymentProviderConnectRequest<'_>,
) -> Result<(), (String, String, i32)>

Tests the currently resolved provider credentials without starting hosted onboarding.