Fix project metadata validate bug

[YangJiao0817]

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Comprehensive Summary of your change

Issue being fixed

Fixes #(issue)

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• Well Written Title and Summary of the PR
• Label the PR as needed. "release-note/ignore-for-release, release-note/new-feature, release-note/update, release-note/enhancement, release-note/community, release-note/breaking-change, release-note/docs, release-note/infra, release-note/deprecation"
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• Made sure tests are passing and test coverage is added if needed.
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[codecov]

Codecov Report

Attention: 2 lines in your changes are missing coverage. Please review.

Comparison is base (2f2a646) 67.54% compared to head (bf488d5) 67.53%.

Additional details and impacted files

@@            Coverage Diff             @@
##             main   #19746      +/-   ##
==========================================
- Coverage   67.54%   67.53%   -0.01%     
==========================================
  Files         991      991              
  Lines      109168   109167       -1     
  Branches     2719     2719              
==========================================
- Hits        73733    73731       -2     
- Misses      31467    31468       +1     
  Partials     3968     3968              

Flag	Coverage Δ
unittests	67.53% <0.00%> (-0.01%)	⬇️

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Files	Coverage Δ
src/server/v2.0/handler/project_metadata.go	0.00% <0.00%> (ø)

... and 3 files with indirect coverage changes

[MinerYang]

lgtm