[cherry-pick]Add Retain image last pull time API test case

[YangJiao0817]

Fix #18618

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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 #18691 (f1e0f31) into release-2.8.0 (31baf31) will decrease coverage by 22.73%.
The diff coverage is n/a.

@@                Coverage Diff                 @@
##           release-2.8.0   #18691       +/-   ##
==================================================
- Coverage          67.38%   44.66%   -22.73%     
==================================================
  Files                984      235      -749     
  Lines             107006    13089    -93917     
  Branches            2670     2670               
==================================================
- Hits               72105     5846    -66259     
+ Misses             31020     6950    -24070     
+ Partials            3881      293     -3588     

Flag	Coverage Δ
unittests	44.66% <ø> (-22.73%)	⬇️

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see 753 files with indirect coverage changes

[chlins]

lgtm