build: replace openbabel-wheel with openbabel

[njzjz-bot]

Problem

• openbabel-wheel has been superseded by the official openbabel package.
• Starting with Open Babel 3.2.0, users can install the Python wheels directly from openbabel on PyPI.

Change

• Replace the openbabel-wheel dependency with openbabel>=3.2.0.

Notes

• This keeps the same Python import path (openbabel) while depending on the upstream package name.

Authored by OpenClaw (model: custom-chat-jinzhezeng-group/gpt-5.5)

[codecov]

Codecov Report

✅ All modified and coverable lines are covered by tests.
✅ Project coverage is 40.69%. Comparing base (2d3e895) to head (b3a4fb5).

Additional details and impacted files

@@            Coverage Diff             @@
##             main     #548      +/-   ##
==========================================
+ Coverage   40.68%   40.69%   +0.01%     
==========================================
  Files          93       93              
  Lines       30328    30328              
==========================================
+ Hits        12339    12343       +4     
+ Misses      17989    17985       -4     

Flag	Coverage Δ
unittests	40.69% <ø> (+0.01%)	⬆️

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