[docs] Fix broken tutorial-doc symlinks in release-1.15

[johnkerl]

Issue and/or context: Post-1.15.0 :( I realized that when I synced main and release-1.15 (modulo necessary differences of course) the files that had been symlinks in main became plain files in release-1.15 -- worse, files containing only the path to their referees. :(

[sc-59686]

Changes: Make these symlinks as they should be.

Notes for Reviewer:

[codecov]

Codecov Report

All modified and coverable lines are covered by tests ✅

Project coverage is 86.26%. Comparing base (a98ff33) to head (313049e).
Report is 3 commits behind head on release-1.15.

Additional details and impacted files

@@               Coverage Diff                @@
##           release-1.15    #3466      +/-   ##
================================================
+ Coverage         86.21%   86.26%   +0.04%     
================================================
  Files                55       55              
  Lines              6311     6311              
================================================
+ Hits               5441     5444       +3     
+ Misses              870      867       -3     

Flag	Coverage Δ
python	86.26% <ø> (+0.04%)	⬆️

Flags with carried forward coverage won't be shown. Click here to find out more.

Components	Coverage Δ
python_api	86.26% <ø> (+0.04%)	⬆️
libtiledbsoma	∅ <ø> (∅)

[johnkerl]

Thanks @ryan-williams !