Fixing logic for delaying setting external user id

We sometimes we don't create a new session if we force quit and come back
within 30 seconds. This caused a bug where we would never send external ids.
To fix this we just need to check that we have called for remote params

Author: emawby

iOS_SDK/OneSignalSDK/Source/OneSignal.m

@@ -2668,7 +2668,7 @@ + (void)setExternalUserId:(NSString *)externalId withExternalIdAuthHashToken:(NS
         return;
 
     // Can't set the external id if init is not done or the app id or user id has not ben set yet
-    if (!performedOnSessionRequest) {
+    if (!_didCallDownloadParameters) {
         // will be sent as part of the registration/on_session request
         pendingExternalUserId = externalId;
         pendingExternalUserIdHashToken = hashToken;