[cherry-pick]Add banner message API test case

[YangJiao0817]

Fix #19271

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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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[chlins]

lgtm

[codecov]

Codecov Report

Merging #19514 (0edc541) into release-2.9.0 (6d81772) will decrease coverage by 22.56%.
Report is 1 commits behind head on release-2.9.0.
The diff coverage is n/a.

@@                Coverage Diff                 @@
##           release-2.9.0   #19514       +/-   ##
==================================================
- Coverage          67.40%   44.85%   -22.56%     
==================================================
  Files                993      244      -749     
  Lines             108932    13416    -95516     
  Branches            2752     2752               
==================================================
- Hits               73430     6018    -67412     
+ Misses             31549     7092    -24457     
+ Partials            3953      306     -3647     

Flag	Coverage Δ
unittests	44.85% <ø> (-22.56%)	⬇️

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see 751 files with indirect coverage changes