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"
• Accepted the DCO. Commits without the DCO will delay acceptance.
• Made sure tests are passing and test coverage is added if needed.
• Considered the docs impact and opened a new docs issue or PR with docs changes if needed in website repository.

[codecov]

Codecov Report

Merging #19510 (cc3074d) into main (193b00b) will decrease coverage by 22.57%.
The diff coverage is n/a.

@@             Coverage Diff             @@
##             main   #19510       +/-   ##
===========================================
- Coverage   67.43%   44.86%   -22.57%     
===========================================
  Files         989      244      -745     
  Lines      108836    13417    -95419     
  Branches     2752     2752               
===========================================
- Hits        73390     6020    -67370     
+ Misses      31482     7093    -24389     
+ Partials     3964      304     -3660     

Flag	Coverage Δ
unittests	44.86% <ø> (-22.57%)	⬇️

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see 746 files with indirect coverage changes

[chlins]

lgtm