fix: CI - merge Android export & compile

[bitsandfoxes]

This addresses the second part of #1975 and builds on top of #1989

This PR attempts to merge exporting the Android Gradle project with its compilation.
With this, the exported build makes use of environment set up with the Unity installation. This effectively removed the need for us to

• manually modifying the exported gradle project https://github.com/getsentry/sentry-unity/blob/main/test/Scripts.Integration.Test/modify-gradle-project.ps1
• manually setting up the runner environment https://github.com/getsentry/sentry-unity/blob/13510397cbcca2195368b175d85cedfda7c8ea30/.github/workflows/ci.yml#L513C1-L537C54

And it allows us to add 2022 back to run on Android.

#skip-changelog

[vaind]

LGTM