Fix pandas warning

[xiki-tempula]

No description provided.

[codecov]

Codecov Report

✅ All modified and coverable lines are covered by tests.
✅ Project coverage is 99.01%. Comparing base (7b36e41) to head (dcfab02).
⚠️ Report is 1 commits behind head on master.

Additional details and impacted files

@@           Coverage Diff           @@
##           master     #448   +/-   ##
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  Coverage   99.01%   99.01%           
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  Files          29       29           
  Lines        2444     2446    +2     
  Branches      464      464           
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+ Hits         2420     2422    +2     
  Misses          2        2           
  Partials       22       22           

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[Copilot]

Pull request overview

This PR addresses pandas warnings by replacing deprecated .apply(lambda x: round(x, prec)) patterns with the modern .round(prec) method, and adding .copy() to chained indexing operations to avoid SettingWithCopyWarning.

Key Changes:

• Replaced .apply(lambda x: round(x, prec)) with .round(prec) for better performance and to eliminate deprecation warnings
• Added .copy() after .iloc indexing to prevent pandas SettingWithCopyWarning
• Refactored multi-column rounding operations to use intermediate variables for clarity

Reviewed changes

Copilot reviewed 2 out of 2 changed files in this pull request and generated no comments.

File	Description
src/alchemlyb/parsing/lammps.py	Updated pandas operations to use modern methods and avoid chained indexing warnings across multiple functions
CHANGES	Added changelog entry documenting the fix for pandas warnings

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[orbeckst]

lgtm, will just add you to CHANGES