DOC: Correct typos in linalg_tutorial.ipynb

[star1327p]

Correct typos in linalg_tutorial.ipynb:
https://einstats.python.arviz.org/en/latest/tutorials/linalg_tutorial.html

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Codecov Report

✅ All modified and coverable lines are covered by tests.
✅ Project coverage is 91.52%. Comparing base (d21153a) to head (79c53cf).
⚠️ Report is 20 commits behind head on main.

Additional details and impacted files

@@            Coverage Diff             @@
##             main      #79      +/-   ##
==========================================
+ Coverage   90.29%   91.52%   +1.23%     
==========================================
  Files           6        6              
  Lines         793      850      +57     
==========================================
+ Hits          716      778      +62     
+ Misses         77       72       -5     

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