build: include vinext in docker build

[hyoban]

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Summary

Fixes #34534

Screenshots

Before	After
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Checklist

• This change requires a documentation update, included: Dify Document
• I understand that this PR may be closed in case there was no previous discussion or issues. (This doesn't apply to typos!)
• I've added a test for each change that was introduced, and I tried as much as possible to make a single atomic change.
• I've updated the documentation accordingly.
• I ran make lint and make type-check (backend) and cd web && npx lint-staged (frontend) to appease the lint gods

[codecov]

Codecov Report

✅ All modified and coverable lines are covered by tests.
✅ Project coverage is 83.75%. Comparing base (4d4265f) to head (a80781b).
⚠️ Report is 1 commits behind head on main.

Additional details and impacted files

@@            Coverage Diff             @@
##             main   #34535      +/-   ##
==========================================
- Coverage   83.75%   83.75%   -0.01%     
==========================================
  Files        4179     4179              
  Lines      176784   176788       +4     
  Branches    35366    35367       +1     
==========================================
+ Hits       148065   148067       +2     
- Misses      25839    25840       +1     
- Partials     2880     2881       +1     

Flag	Coverage Δ
api	82.36% <ø> (-0.01%)	⬇️
web	85.46% <100.00%> (+<0.01%)	⬆️

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