Fix incorrect rest response header and demo double path error

[suncairong163]

What is the purpose of the change

fix #13640
#13665

Brief changelog

Verifying this change

@AlbumenJ

Checklist

• Make sure there is a GitHub_issue field for the change (usually before you start working on it). Trivial changes like typos do not require a GitHub issue. Your pull request should address just this issue, without pulling in other changes - one PR resolves one issue.
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[codecov-commenter]

Codecov Report

All modified and coverable lines are covered by tests ✅

Project coverage is 70.34%. Comparing base (99613a1) to head (11bff8a).

Additional details and impacted files

@@            Coverage Diff             @@
##              3.2   #13789      +/-   ##
==========================================
+ Coverage   70.32%   70.34%   +0.01%     
==========================================
  Files        1606     1606              
  Lines       70022    70030       +8     
  Branches    10102    10106       +4     
==========================================
+ Hits        49246    49263      +17     
+ Misses      16141    16128      -13     
- Partials     4635     4639       +4     

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[AlbumenJ]

LGTM
@CrazyHZM PTAL

[CrazyHZM]

Please remove it.

[sonarcloud]

Quality Gate passed

Issues
0 New issues

Measures
0 Security Hotspots
80.8% Coverage on New Code
0.0% Duplication on New Code

See analysis details on SonarCloud