Added support for iOS13 with apns-push-type

[McPo]

apns-push-type is now a required key in the payload starting from iOS 13, without this notifications can be delayed or dropped altogether.

https://developer.apple.com/documentation/usernotifications/setting_up_a_remote_notification_server/sending_notification_requests_to_apns?language=objc

[codecov-io]

Codecov Report

Merging #424 into master will decrease coverage by 0.12%.
The diff coverage is 0%.

@@            Coverage Diff             @@
##           master     #424      +/-   ##
==========================================
- Coverage    84.1%   83.97%   -0.13%     
==========================================
  Files          19       19              
  Lines        1346     1348       +2     
==========================================
  Hits         1132     1132              
- Misses        172      173       +1     
- Partials       42       43       +1

Impacted Files	Coverage Δ
gorush/notification.go	100% <ø> (ø)	⬆️
gorush/notification_apns.go	84.26% <0%> (-0.96%)	⬇️

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[ghost]

It is better to specify two values "alert", "background" because only they are valid

[McPo]

I'm not au fait with golang, but would have thought that the "casting" to apns2.EPushType would raise an error if it was an unknown. no? And I would have assumed its probably better to raise an error in such a case than just ignore it.

[HelmiRifai]

@appleboy will there be a release soon with this?

[aksioto]

This field missed in protobuf file for grpc

[McPo]

Just noting this here. There appears to a be a third (currently undocumented, due to oversight) type called "voip". As we are running into the same issues described here https://forums.developer.apple.com/thread/123076. This will require a validation change in sideshow/apns2, which Ill make a PR. Just a heads up.

[McPo]

Turns out the PR and upstream lib doesn't actually validate the value. So we can just pass "voip" as it is now.