Include host policy instances to Africa's Talking payments connector (#406)

* Update Africa's Talking Payments connector

* Include host policy instances to Africa's Talking payments connector

Co-authored-by: Crispin Kipruto <crispin.kipruto@africastalking.com>

Author: crispinkoech

certified-connectors/Africa's Talking Payments/apiProperties.json

@@ -38,6 +38,15 @@
     },
     "iconBrandColor": "#fc9206",
     "capabilities": [],
+    "policyTemplateInstances": [
+      {
+        "templateId": "dynamichosturl",
+        "title": "Host URL",
+        "parameters": {
+          "x-ms-apimTemplateParameter.urlTemplate": "https://@connectionParameters('environment').africastalking.com"
+        }
+      }
+    ],
     "publisher": "Africa's Talking",
     "stackOwner": "Africa's Talking"
   }