BrAPI: fix PUT /trials response returning trialName in trialDescription

[shbrainard]

Summary

• One-line fix in lib/CXGN/BrAPI/v2/Trials.pm. The PUT response was returning $folder->name in the trialDescription field of the response payload, with a comment "description doesn't exist".
• The DB write earlier in the same function ($folder->description($description || '') at line 322) was correct, so persistence has always been fine. Only the response payload was wrong.
• Read the description directly from the project row instead.
• Any BrAPI client that uses the PUT response to update its in-memory representation of the trial silently overwrites its local trialDescription with the trial name.

Reproducer

1. POST /brapi/v2/trials to create a trial.
2. PUT /brapi/v2/trials/{id} with the existing body and a modified trialDescription.
3. The PUT response's trialDescription field contains the trial's name, not the value sent.
4. A subsequent GET returns the correct (sent) value.

Verification

Reproduced and verified the fix on the breedbase_dockerfile dev stack at sgn-454.0: PUT round-trip now returns the correct trialDescription; subsequent GET confirms the database value matches.