fix: Added proper return messages for drop tasks

[nish112022]

issue: #37249

This is for drop collection,drop partition and drop index tasks

[sre-ci-robot]

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[nish112022]

rerun go-sdk

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@nish112022 go-sdk check failed, comment rerun go-sdk can trigger the job again.

[codecov]

Codecov Report

All modified and coverable lines are covered by tests ✅

Project coverage is 67.12%. Comparing base (86b9c3e) to head (086c27c).
Report is 8 commits behind head on master.

Additional details and impacted files

@@             Coverage Diff             @@
##           master   #37251       +/-   ##
===========================================
- Coverage   83.15%   67.12%   -16.03%     
===========================================
  Files        1029      290      -739     
  Lines      157251    25435   -131816     
===========================================
- Hits       130764    17074   -113690     
+ Misses      21322     8361    -12961     
+ Partials     5165        0     -5165     

Components	Coverage Δ
Client	∅ <ø> (∅)
Core	67.12% <ø> (∅)
Go	∅ <ø> (∅)

see 1319 files with indirect coverage changes

[nish112022]

/run-cpu-e2e

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@nish112022 E2e jenkins job failed, comment /run-cpu-e2e can trigger the job again.

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@nish112022 go-sdk check failed, comment rerun go-sdk can trigger the job again.

[mergify]

@nish112022 E2e jenkins job failed, comment /run-cpu-e2e can trigger the job again.