Provide cache context for UserCountry condition

the following error occurs with Drupal 10.2.6 and php8.2:

Deprecated function: sha1(): Passing null to parameter #1 ($string) of type string is deprecated in Drupal\smart_ip\CacheContext\CountryCodeCacheContext->getContext() (line 47 of modules/contrib/smart_ip/src/CacheContext/CountryCodeCacheContext.php).
Drupal\smart_ip\CacheContext\CountryCodeCacheContext->getContext(NULL) (Line: 123)
Drupal\Core\Cache\Context\CacheContextsManager->convertTokensToKeys(Array) (Line: 244)
Drupal\Core\Cache\VariationCache->createCacheIdFast(Array, Object) (Line: 179)
Drupal\Core\Cache\VariationCache->getRedirectChain(Array, Object) (Line: 35)
Drupal\Core\Cache\VariationCache->get(Array, Object) (Line: 142)
Drupal\dynamic_page_cache\EventSubscriber\DynamicPageCacheSubscriber->onRequest(Object, 'kernel.request', Object)
call_user_func(Array, Object, 'kernel.request', Object) (Line: 111)
Drupal\Component\EventDispatcher\ContainerAwareEventDispatcher->dispatch(Object, 'kernel.request') (Line: 157)
Symfony\Component\HttpKernel\HttpKernel->handleRaw(Object, 1) (Line: 76)
Symfony\Component\HttpKernel\HttpKernel->handle(Object, 1, 1) (Line: 58)
Drupal\Core\StackMiddleware\Session->handle(Object, 1, 1) (Line: 48)
Drupal\Core\StackMiddleware\KernelPreHandle->handle(Object, 1, 1) (Line: 28)
Drupal\Core\StackMiddleware\ContentLength->handle(Object, 1, 1) (Line: 32)
Drupal\big_pipe\StackMiddleware\ContentLength->handle(Object, 1, 1) (Line: 106)
Drupal\page_cache\StackMiddleware\PageCache->pass(Object, 1, 1) (Line: 85)
Drupal\page_cache\StackMiddleware\PageCache->handle(Object, 1, 1) (Line: 48)
Drupal\Core\StackMiddleware\ReverseProxyMiddleware->handle(Object, 1, 1) (Line: 51)
Drupal\Core\StackMiddleware\NegotiationMiddleware->handle(Object, 1, 1) (Line: 36)
Drupal\Core\StackMiddleware\AjaxPageState->handle(Object, 1, 1) (Line: 51)
Drupal\Core\StackMiddleware\StackedHttpKernel->handle(Object, 1, 1) (Line: 704)
Drupal\Core\DrupalKernel->handle(Object) (Line: 19)