fix: 🐛 Warning http_response_header deprecated

Replaces http_response_header with http_get_last_response_headers

✅ Closes: #18

Author: tsamaya

src/AbstractGeocoder.php

@@ -71,8 +71,8 @@ protected function getJSONByFopen($query)
         if ($ret === false) {
             /** NOTE: https://github.com/phpstan/phpstan/issues/3213 */
             /** @phpstan-ignore-next-line */
-            if (isset($http_response_header) && is_array($http_response_header)) {
-                $error_message = $http_response_header[0];
+            if (isset($http_get_last_response_headers) && is_array($http_get_last_response_headers)) {
+                $error_message = $http_get_last_response_headers[0];
                 if ($error = error_get_last()) {
                     $error_message = $error['message'];
                 }