Upgrade vm_service to get access to serialization of snapshot an optimization for memory footprint.

[polina-c]

Prerequisite: https://github.com/flutter/flutter/pull/144783

[auto-submit[bot]]

auto label is removed for flutter/devtools/7331, due to - The status or check suite devtools_app integration-test integration_dart2js - flutter - shard 3/3 has failed. Please fix the issues identified (or deflake) before re-applying this label.