website/docs: update geoip and asn example to use the proper syntax (#10249)

website/docs/policies/expression.mdx

@@ -56,13 +56,13 @@ import Objects from "../expressions/_objects.md";
 -   `geoip`: GeoIP object, see [GeoIP](https://geoip2.readthedocs.io/en/latest/#geoip2.models.City)
 
     ```python
-    return context["geoip"].country.iso_code == "US"
+    return context["geoip"]["country"]["iso_code"] == "US"
     ```
 
 -   `asn`: ASN object, see [GeoIP](https://geoip2.readthedocs.io/en/latest/#geoip2.models.ASN)
 
     ```python
-    return context["asn"].autonomous_system_number == 64496
+    return context["asn"]["autonomous_system_number"] == 64496
     ```
 
 -   `ak_is_sso_flow`: Boolean which is true if request was initiated by authenticating through an external provider.