Get rid of hard coded string for aud in jwt

Author: kookster

app/models/apple/api.rb

@@ -1,5 +1,8 @@
 # frozen_string_literal: true
 
+# NOTE: This code does not connect directly to Apple, a bridge lambda is used in between to handle communication and API calls.
+# This is not an official Apple API client, and to use Apple API you will need to have your own agreement with Apple to access their APIs.
+
 module Apple
   class Api
     ERROR_RETRIES = 3
@@ -30,6 +33,10 @@ def self.api_base
       ENV["APPLE_PODCASTS_CONNECT_API_URL"]
     end
 
+    def self.api_aud_name
+      ENV["APPLE_PODCASTS_CONNECT_AUD_NAME"]
+    end
+
     def self.from_key(apple_key)
       new(provider_id: apple_key.provider_id,
         key_id: apple_key.key_id,
@@ -72,7 +79,7 @@ def jwt_payload
 
       {iss: provider_id,
        exp: now.to_i + (60 * 15),
-       aud: "podcastsconnect-v1"}
+       aud: self.class.api_aud_name}
     end
 
     def jwt_headers