drop deprecated allow_frozen argument from apply_to_collection call

[deependujha]

What does this PR do?

Fixes #21577
depends on Lightning-AI/utilities#499

allow_frozen is now a deprecated no-op in lightning-utilities (frozen dataclasses are reconstructed automatically), so this removes the now-redundant argument from the _optimizer_to_device call to avoid the deprecation warning.

Before submitting

• Was this discussed/agreed via a GitHub issue? (not for typos and docs)
• Did you read the contributor guideline, Pull Request section?
• Did you make sure your PR does only one thing, instead of bundling different changes together?
• Did you make sure to update the documentation with your changes? (if necessary)
• Did you write any new necessary tests? (not for typos and docs)
• Did you verify new and existing tests pass locally with your changes?
• Did you list all the breaking changes introduced by this pull request?
• Did you update the CHANGELOG? (not for typos, docs, test updates, or minor internal changes/refactors)

PR review

Anyone in the community is welcome to review the PR.
Before you start reviewing, make sure you have read the review guidelines. In short, see the following bullet-list:

Reviewer checklist

• Is this pull request ready for review? (if not, please submit in draft mode)
• Check that all items from Before submitting are resolved
• Make sure the title is self-explanatory and the description concisely explains the PR
• Add labels and milestones (and optionally projects) to the PR so it can be classified

[codecov-commenter]

⚠️ Please install the to ensure uploads and comments are reliably processed by Codecov.

Codecov Report

❌ Patch coverage is 0% with 1 line in your changes missing coverage. Please review.
✅ Project coverage is 87%. Comparing base (fe6b1cc) to head (8cc5880).
❗ Your organization needs to install the Codecov GitHub app to enable full functionality.

Additional details and impacted files

@@           Coverage Diff           @@
##           master   #21781   +/-   ##
=======================================
- Coverage      87%      87%   -0%     
=======================================
  Files         270      270           
  Lines       24005    24005           
=======================================
- Hits        20776    20773    -3     
- Misses       3229     3232    +3     

[deependujha]

failing tests are expected to be fixed after Lightning-AI/utilities#499 is merged, and a new version is released.