Unpin polars

[larsevj]

Issue
Resolves #12218

• PR title captures the intent of the changes, and is fitting for release notes.
• Added appropriate release note label
• Commit history is consistent and clean, in line with the contribution guidelines.
• Make sure unit tests pass locally after every commit (git rebase -i main --exec 'just rapid-tests')

When applicable

• When there are user facing changes: Updated documentation
• New behavior or changes to existing untested code: Ensured that unit tests are added (See Ground Rules).
• Large PR: Prepare changes in small commits for more convenient review
• Bug fix: Add regression test for the bug
• Bug fix: Add backport label to latest release (format: 'backport release-branch-name')

[larsevj]

Tests fail due to bug in polars, will need to wait for 1.26.1 release.

[larsevj]

Now it fails on the following issue:
pola-rs/polars#25732

Could maybe reevaluate if there are better ways of applying the transformations.