Cram tests fail in traits due to results changing slightly going from treetime v0.11.0 to v0.11.1

[corneliusroemer]

Current Behavior

We now allow treetime v0.11 as well as v0.10. Tests passed when treetime v0.11.0 was used (in PR), but by the time I merged yesterday, we had released treetime v0.11.1 and now tests fail.

Two cram tests that check for numerical outputs now fail as the outputs are more different than we allow.

The test failures are either a) as intended and caused by small code changes in treetime in which case we should relax our tests to be less strict on numerical results or b) tests reveal something unexpected happening in treetime.

It's easy to relax the tests but better to check with @rneher whether the differences we see are acceptable and expected.

Link to failing CI run line: https://github.com/nextstrain/augur/actions/runs/6182505169/job/16782376608#step:9:16

Context

PR CI run with treetime 0.11.0: https://github.com/nextstrain/augur/actions/runs/6112059062/job/16588703446#step:5:505
Failing merge CI run with treetime 0.11.1: https://github.com/nextstrain/augur/actions/runs/6182505169/job/16782376608#step:5:534