[cherry-pick]Add Referrers API testcase

[YangJiao0817]

Fix #18617

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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

Merging #18776 (3bbcef6) into release-2.8.0 (450e7e7) will decrease coverage by 22.60%.
The diff coverage is n/a.

@@                Coverage Diff                 @@
##           release-2.8.0   #18776       +/-   ##
==================================================
- Coverage          67.34%   44.75%   -22.60%     
==================================================
  Files                984      235      -749     
  Lines             107026    13089    -93937     
  Branches            2670     2670               
==================================================
- Hits               72082     5858    -66224     
+ Misses             31062     6936    -24126     
+ Partials            3882      295     -3587     

Flag	Coverage Δ
unittests	44.75% <ø> (-22.60%)	⬇️

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see 750 files with indirect coverage changes

[wy65701436]

lgtm