Add some logging for --unload-on-kill keyboard interrupt

[saikishor]

Add some meaningful information for the --unload-on-kill options.

This might be interesting to have to introspect #2063, I'm not able to reproduce this locally even after 300+ runs

[codecov]

Codecov Report

Attention: Patch coverage is 66.66667% with 1 line in your changes missing coverage. Please review.

Project coverage is 89.51%. Comparing base (bfbedd2) to head (51ea19c).
Report is 1 commits behind head on master.

Files with missing lines	Patch %	Lines
controller_manager/controller_manager/spawner.py	66.66%	1 Missing ⚠️

Additional details and impacted files

@@            Coverage Diff             @@
##           master    #2097      +/-   ##
==========================================
- Coverage   89.59%   89.51%   -0.08%     
==========================================
  Files         139      139              
  Lines       15222    15227       +5     
  Branches     1290     1290              
==========================================
- Hits        13638    13631       -7     
- Misses       1096     1105       +9     
- Partials      488      491       +3     

Flag	Coverage Δ
unittests	89.51% <66.66%> (-0.08%)	⬇️

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

Files with missing lines	Coverage Δ
controller_manager/controller_manager/spawner.py	74.45% <66.66%> (-0.37%)	⬇️

... and 3 files with indirect coverage changes

🚀 New features to boost your workflow:

• ❄ Test Analytics: Detect flaky tests, report on failures, and find test suite problems.