[cherry-pick] fix robot deletion event (#21234)

[wy65701436]

• fix robot deletion event

• resolve comments

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Comprehensive Summary of your change

Issue being fixed

Fixes #(issue)

Please indicate you've done the following:

• 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

Attention: Patch coverage is 40.00000% with 9 lines in your changes missing coverage. Please review.

Please upload report for BASE (release-2.12.0@7201b3b). Learn more about missing BASE report.

Files with missing lines	Patch %	Lines
src/controller/event/metadata/robot.go	14.28%	3 Missing and 3 partials ⚠️
src/controller/robot/controller.go	57.14%	2 Missing and 1 partial ⚠️

Additional details and impacted files

@@                Coverage Diff                @@
##             release-2.12.0   #21272   +/-   ##
=================================================
  Coverage                  ?   66.07%           
=================================================
  Files                     ?     1049           
  Lines                     ?   114656           
  Branches                  ?     2867           
=================================================
  Hits                      ?    75764           
  Misses                    ?    34745           
  Partials                  ?     4147           

Flag	Coverage Δ
unittests	66.07% <40.00%> (?)

Flags with carried forward coverage won't be shown. Click here to find out more.

Files with missing lines	Coverage Δ
src/controller/robot/model.go	100.00% <ø> (ø)
src/controller/scan/callback.go	60.86% <100.00%> (ø)
src/controller/robot/controller.go	55.74% <57.14%> (ø)
src/controller/event/metadata/robot.go	70.96% <14.28%> (ø)

[MinerYang]

lgtm