Updated to Gradle 8 and AGP 8

[jkasten2]

Description

One Line Summary

Update both SDK project and example to use the latest Gradle and AGP (Android Gradle Plugin) versions, currently 8.x.

Details

Motivation

Our Gradle version and AGP versions are getting out of date. It is starting to cause issues such as having to configure a system JDK of 17 instead of using 21 that ships with the newest Android Studio. Updating before trying to automate publishing, as otherwise we will test publishing again.

Scope

Only changes require to build with the latest Gradle and AGP versions.

Testing

Unit testing

• TODO - Publishing is untested and may require some changes yet.

Manual testing

Ensured example project builds and runs on an Android emulator.

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
  • If it is hard to explain how any codes changes are related to each other then it most likely needs to be more than one PR
• 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.
  • Simplify with less code, followed by splitting up code into well named functions and variables, followed by adding comments to the code.
• I have reviewed this PR myself, ensuring it meets each checklist item
  • WIP (Work In Progress) is ok, but explain what is still in progress and what you would like feedback on. Start the PR title with "WIP" to indicate this.

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