test: Add scheduling suspension e2e

[Monokaix]

What type of PR is this?
/kind feature

What this PR does / why we need it:
Add e2e for #5937
Which issue(s) this PR fixes:
Fixes #

Special notes for your reviewer:

Does this PR introduce a user-facing change?:

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Codecov Report

All modified and coverable lines are covered by tests ✅

Project coverage is 48.38%. Comparing base (a891673) to head (6fdb137).
Report is 2 commits behind head on master.

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Additional details and impacted files

@@            Coverage Diff             @@
##           master    #6012      +/-   ##
==========================================
- Coverage   48.39%   48.38%   -0.01%     
==========================================
  Files         665      665              
  Lines       54811    54811              
==========================================
- Hits        26525    26522       -3     
- Misses      26568    26570       +2     
- Partials     1718     1719       +1     

Flag	Coverage Δ
unittests	48.38% <ø> (-0.01%)	⬇️

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