[CI] Replace `reactivecircus/android-emulator-runner` | Resolve flaking timeout

[AlexV525]

During the development of https://github.com/dart-lang/http/pull/1104, the test frequently fails without showing an obvious reason, which makes it hard to track the root cause. We should find a more stable solution or find the root cause of the timeout.

[dnys1]

I ran into the same issue working on Amplify Flutter and rewrote reactivecircus's GH action in Dart to try and resolve the flakiness.

The main insight I gathered was the overwhelming performance and stability gained from hardware acceleration, which is only available on macos-xl runners and GitHub's large runners. Using those, hardware acceleration can be enabled relatively easily and the reactivecircus action should be sufficient.