Initial baseline diagnostics output with`-u` not canonified

[awelzel]

I've ran into this a few times now and continue to be confused if it's my canonifier not working right, or btest not showing me what the baseline will actually look like. IMO the UX would be better if the initial diagnostics output showed the canonified baseline.

Workflow:

• Write a new test with a canonifier
• run with btest -d -u new.test
• The first update shown with "diagnostics" presents the non-canonified version:

$ btest -d scripts/base/frameworks/cluster/leftover-log-rotation-multi-logger.zeek -u
[  0%] scripts.base.frameworks.cluster.leftover-log-rotation-multi-logger ... failed
>> Type 'c' to continue, 'd' to see diagnostics, 'u' to update baseline, and 'a' to abort
(pressing d)
== File ===============================
./log-queue/conn__2023-06-13-08-16-52__2023-06-13-08-16-52__log_suffix=logger-2__.log
./log-queue/dns__2023-06-13-08-16-52__2023-06-13-08-16-52__log_suffix=logger-2__.log
leftover conn log
leftover dns log
=======================================
(pressing q)
>> Type 'c' to continue, 'd' to see diagnostics, 'u' to update baseline, and 'a' to abort.
(pressing u for update)
>> Updating baseline ...
all 1 tests successful

• Checking the just stored baseline shows it was actually canonified even if the diagnostics output doesn't show it.

$ cat Baseline/scripts.base.frameworks.cluster.leftover-log-rotation-multi-logger/out
### BTest baseline data generated by btest-diff. Do not edit. Use "btest -U/-u" to update. Requires BTest >= 0.63.
./log-queue/conn__XXXX-XX-XX-XX-XX-XX__XXXX-XX-XX-XX-XX-XX__log_suffix=logger-2__.log
./log-queue/dns__XXXX-XX-XX-XX-XX-XX__XXXX-XX-XX-XX-XX-XX__log_suffix=logger-2__.log
leftover conn log
leftover dns log

Interestingly, updating an existing baseline shows the canonified diff. It's probably a small tweak somewhere.