fix(infra): use correct version number for flagsmith workflows

[matthewelwell]

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Changes

Fixes the definition of the revision for checking out the flagsmith-workflows repository.

How did you test this code?

TBD with release.

[vercel]

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Name	Status	Preview	Comments	Updated (UTC)
docs	✅ Ready (Inspect)	Visit Preview		Feb 13, 2024 11:06am
flagsmith-frontend-preview	✅ Ready (Inspect)	Visit Preview	💬 Add feedback	Feb 13, 2024 11:06am
flagsmith-frontend-staging	✅ Ready (Inspect)	Visit Preview		Feb 13, 2024 11:06am

[github-actions]

Uffizzi Preview deployment-46446 was deleted.

[codecov-commenter]

Codecov Report

All modified and coverable lines are covered by tests ✅

Comparison is base (ad3ce0e) 95.91% compared to head (4a51f96) 95.91%.
Report is 1 commits behind head on main.

Additional details and impacted files

@@           Coverage Diff           @@
##             main    #3408   +/-   ##
=======================================
  Coverage   95.91%   95.91%           
=======================================
  Files        1081     1081           
  Lines       33574    33574           
=======================================
  Hits        32204    32204           
  Misses       1370     1370           

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