Fix MeshXY's .coords method

[pt331]

Description

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Checklist

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• Included a What's New entry
• Incorporated type hints in any changed code
• Checked if tests need updating
• Checked if benchmarks need updating
• Checked if documentation needs updating
  • Docstrings (we love code examples!)
  • User Manual pages
• Checked if dependencies need updating
• Confirmed that the GitHub 'checks' on this PR are passing ✅
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[codecov]

Codecov Report

✅ All modified and coverable lines are covered by tests.
✅ Project coverage is 90.15%. Comparing base (9c5eb0a) to head (5be6d48).
⚠️ Report is 2 commits behind head on main.

Additional details and impacted files

@@           Coverage Diff           @@
##             main    #7185   +/-   ##
=======================================
  Coverage   90.15%   90.15%           
=======================================
  Files          91       91           
  Lines       24989    24990    +1     
  Branches     4687     4686    -1     
=======================================
+ Hits        22528    22529    +1     
  Misses       1683     1683           
  Partials      778      778           

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