`application_start` event is not sent for Datadog sdk version >= 2.6.0

[saad352]

Describe the bug

Datadog SDK sends action of type application_start. This is working fine until the version 2.5.1 but this event is not being sent from version 2.6.0 onwards.

More info I have scanned and tried to debug through the sdk code. The data for application_start seems to be gathered properly and written using FileWriter but I don't see data in the RUM Web dashboard. So my guess is that it is being collected but not sent. More over I see this code change to send N batches sequentially. Not sure but could be related to this. My reasoning for pointing to this PR is that we are only missing the first event which is application_start, the rest of the events I see are fine. So may be it is missing the first event and sending the later ones just fine? Or may be something else.

Reproduction steps

Use ddsdk version 2.5.1 and we can see the action application_start but when bumping to 2.6.0 the event does not seems to be sent.

SDK logs

N/A

Expected behavior

application_start event should be seen in the RUM dashboard.

Affected SDK versions

>= 2.6.0

Latest working SDK version

2.5.1

Did you confirm if the latest SDK version fixes the bug?

Yes, it does not fix the issue.

Integration Methods

Cocoapods

Xcode Version

15.4

Swift Version

swiftlang-5.10.0.13

MacOS Version

No response

Deployment Target

iOS 17

Device Information

All

Other relevant information

No response