Order global tracks by the CPU score

Currently we don't do any special ordering for the global tracks. So they are displayed as the same order as their order in the profile data. We already have a CPU score to determine which track should be shown by default. We can use the same number to order the tracks, so the one people need will be at the top (right after the parent process).

Currently thinking about experimenting with making the parent process at the top all the time, but happy to get any feedback.

┆Issue is synchronized with this [Jira Task](https://mozilla-hub.atlassian.net/browse/FP-764)