refactor: OPTIC-1270: Remove Stale Feature Flag - fflag_feat_front_prod_309_choice_hint_080523_short

[luarmr]

PR fulfills these requirements

• Commit message(s) and PR title follows the format [fix|feat|ci|chore|doc]: TICKET-ID: Short description of change made ex. fix: DEV-XXXX: Removed inconsistent code usage causing intermittent errors
• Tests for the changes have been added/updated (for bug fixes/features)
• Docs have been added/updated (for bug fixes/features)
• Best efforts were made to ensure docs/code are concise and coherent (checked for spelling/grammatical errors, commented out code, debug logs etc.)
• Self-reviewed and ran all changes on a local instance (for bug fixes/features)

Change has impacts in these area(s)

(check all that apply)

• Product design
• Backend (Database)
• Backend (API)
• Frontend

Describe the reason for change

Removing a feature flag that has been stale for a while allows us to remove another feature flag that appears to be related in LD.

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[codecov]

Codecov Report

All modified and coverable lines are covered by tests ✅

Project coverage is 76.73%. Comparing base (70a008f) to head (a48fe3a).
Report is 7 commits behind head on develop.

Additional details and impacted files

@@           Coverage Diff            @@
##           develop    #6576   +/-   ##
========================================
  Coverage    76.72%   76.73%           
========================================
  Files          169      169           
  Lines        13818    13818           
========================================
+ Hits         10602    10603    +1     
+ Misses        3216     3215    -1     

Flag	Coverage Δ
pytests	76.73% <ø> (+<0.01%)	⬆️

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