Fixes#948
This PR does the following:
1. Changes the trigger for the PR comment updater from the cron method to workflow_run, triggered on completion of the test cases. This should remove the delay between the completion of the performance tests and the updating of the corresponding comment in the PR.
2. Separates the integrity check and performance check into separate workflows and allows them to run in parallel. This will allow the project to take advantage of multiple CI runners if they're available (which appears to be the case).
In addition, this fixes an issue with post-merge undeleted/updated branches on PRs. The current "cron" method causes the CI to run the pr-update job over and over forever, unnecessarily.
As described in github/docs#799, and the [github docs](https://docs.github.com/en/actions/reference/events-that-trigger-workflows#workflow_run), a `workflow_run` trigger will only fire when the workflow file is on the main branch. Thus, this change will not fire the PR updater on this PR. Thus there's no way to test this working properly without merging onto master and then testing on one of the other PRs.
* Trims SSD drives, flushes cache before each performance test. Unfortunately these are still incomplete -- need to use real hardware machines for all these to take effect.
* A bit more output in PR updater
Include closed PRs in the update cycle, because there could be a case that PR got closed before the job had a chance to finish, and we should still update it.
Turned out that some update jobs failed due to
```
{
"message": "Bad credentials",
"documentation_url": "https://developer.github.com/v3"
}
```
This is probably due to credentials expiring (long workflow startup?),
or some internal github issue.
For now, removing authenticated `curl` calls because most
of them can be done anonymously, and keeping them only when needed.
* delete output escaping (forgot to remove it -- was used for the older system)
* stop early if there are no pull requests (e.g. in case this is a fork)
A cron-based approach to find pull requests, possibly from forks,
that finished profiling, and post their results as comments.
See in-depth explanation of how this works at
https://github.com/nyurik/auto_pr_comments_from_forks
