This enhances external-tests logic, ensuring that destructive tests
have retries and some context to pinpoint failures, and that failed-state
services are reset between iterations.
And I made a few more API tweaks, such as supporting `Path`
objects directly and also not needing e.g. `commit = commit`, see
- cfa7c71126
- 679bce4cc7
This adds infrastructure to the Rust test suite for destructive
tests, and adds a new `transactionality` test which runs
rpm-ostree in a loop (along with `ostree-finalize-staged`) and
repeatedly uses either `kill -9`, `reboot` and `reboot -ff`.
The main goal here is to flush out any "logic errors".
So far I've validated that this passes a lot of cycles
using
```
$ kola run --qemu-image=fastbuild-fedora-coreos-ostree-qemu.qcow2 ext.ostree.destructive-rs.transactionality --debug --multiply 8 --parallel 4
```
a number of times.
Colin Walters
Luca BRUNO