style: fix pyink formatting on main (2 files)

[Perseus14]

Main currently fails the CI pyink check (.github/workflows/CPUTests.yml) on 2 files introduced by recent commits (#487 / 601381be):

• src/maxdiffusion/configuration_utils.py
• src/maxdiffusion/trainers/wan_trainer_2_2.py

This makes CPU CI red on PRs rebased onto main. This PR runs pyink --pyink-indentation=2 --line-length=125 on those 2 files (formatting only, no functional changes).

Verified: pyink src/maxdiffusion end_to_end --check --diff --pyink-indentation=2 --line-length=125 -> 352 files would be left unchanged.

[github-actions]

e2e testgrid: https://8bcf50593faf4ea38060e236169827e5-dot-us-central1.composer.googleusercontent.com/dags/maxdiffusion_tpu_e2e/grid

[gemini-code-assist]

Code Review

This pull request introduces minor formatting improvements, including consolidating a multi-line list comprehension into a single line in configuration_utils.py and adding an empty line before a nested function definition in wan_trainer_2_2.py for better readability. There are no review comments, and I have no feedback to provide.