fix: remove unnecessary call to fetch courses on course authoring page

[saadyousafarbi]

Description

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[codecov]

Codecov Report

All modified and coverable lines are covered by tests ✅

Project coverage is 93.39%. Comparing base (26c919a) to head (f816705).

Additional details and impacted files

@@            Coverage Diff             @@
##           master    #1714      +/-   ##
==========================================
- Coverage   93.39%   93.39%   -0.01%     
==========================================
  Files        1110     1110              
  Lines       22284    22282       -2     
  Branches     4811     4725      -86     
==========================================
- Hits        20812    20810       -2     
- Misses       1400     1407       +7     
+ Partials       72       65       -7     

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