Add details about ic, broken, flaky, and unstable checks to merge records (#106162)
At the moment, we only record the list of pending and failed check on Rockset merge records. This is enough to compute the force merge KPI(s), but isn't enough for more in-depth analysis on what happened at the time of the merge:
* If the number of `ok_failed_checks` is less than `ok_failed_checks_threshold`, the list of `failed_checks` would be empty (expectedly). So Rockset would only record an empty list.
* We support retry in PR, so the classifications on Dr.CI could be different than what dev observed at the time of the merge if retry completed successfully
### Testing
`python .github/scripts/trymerge.py --comment-id 1654010315 106095 --dry-run` (need to comment out some of the code to actually write a test record to Rockset), then manually verify it with
```
SELECT
*
FROM
commons.merges
WHERE
pr_num = 106095
```
to see that `ignore_current_checks`, `broken_trunk_checks`, `flaky_checks`, and `unstable_checks` shows up correctly
Pull Request resolved: https://github.com/pytorch/pytorch/pull/106162
Approved by: https://github.com/clee2000
