[Fix] Include OneSignalConfig.androidlib meta files

[shepherd-l]

Description

One Line Summary

Includes .meta files in OneSignalConfig.androidlib to prevent asset from being ignored

Details

Motivation

Fixes compile time errors in Android package - all files in Packages/com.onesignal.unity.android/Editor/OneSignalConfig.androidlib/:

Packages/com.onesignal.unity.android/Editor/OneSignalConfig.androidlib/AndroidManifest.xml has no meta file, but it's in an immutable folder. The asset will be ignored.

Scope

Affects Unity Editor 2021 versions. Reproducible in 2021.3 but I was unable to reproduce in 2022.3.10.

Unity made a change where meta files don't need to be included in plugins for newer versions:
https://forum.unity.com/threads/loadable-plugin-directory-import-behaviour-change-androidlib-bundle-framework-and-plugin.1381113/

It looks like the change does not apply to 2021 because of the compile errors, so it looks like we need to include meta files in our OneSignalConfig.androidlib for 2021 support.

Testing

Manual testing

Tested OneSignal initialization, app build with Unity 2021.3.0f1 and 2022.3.10f1 of the OneSignal example app on a emulated Pixel 4 with Android 12.

Affected code checklist

• Notifications
  • Display
  • Open
  • Push Processing
  • Confirm Deliveries
• Outcomes
• Sessions
• In-App Messaging
• REST API requests
• Public API changes

Checklist

Overview

• I have filled out all REQUIRED sections above
• PR does one thing
• Any Public API changes are explained in the PR details and conform to existing APIs

Testing

• I have included test coverage for these changes, or explained why they are not needed
• All automated tests pass, or I explained why that is not possible
• I have personally tested this on my device, or explained why that is not possible

Final pass

• Code is as readable as possible.
• I have reviewed this PR myself, ensuring it meets each checklist item

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