fix: stacklevel of MapReduce padding warning

[rg936672]

PR Type

• Bugfix

Description

MapReduce's warning about padding invariance is now raised at the correct stacklevel (so it appears at the call site, rather than in the internals of Equinox.

How Has This Been Tested?

Have checked the warning is raised at the call site.

Does this PR introduce a breaking change?

No.

Checklist before requesting a review

• I have made sure that my PR is not a duplicate.
• My code follows the style guidelines of this project.
• I have ensured my code is easy to understand, including docstrings and comments where necessary.
• I have performed a self-review of my code.
• I have made corresponding changes to the documentation.
• My changes generate no new warnings.
• New and existing unit tests pass locally with my changes.
• Any dependent changes have been merged and published in downstream modules.
• I have updated CHANGELOG.md, if appropriate.

[github-actions]

Performance review

Commit 012a062 - Merge 86457b6 into 54a2228

No significant changes to performance.

[github-actions]

Performance review

Commit b94263a - Merge 9684213 into 54a2228

No significant changes to performance.