ASOAPI: delete resources removed from spec

[nojnhuh]

What type of PR is this?
/kind feature

What this PR does / why we need it:

This PR adds the logic for ASOAPI resources to delete resources that are removed from spec.resources through an update like we did for the existing CAPZ APIs in #4506.

Which issue(s) this PR fixes (optional, in fixes #<issue number>(, fixes #<issue_number>, ...) format, will close the issue(s) when PR gets merged):
Part of #4713

Special notes for your reviewer:

• cherry-pick candidate

TODOs:

• squashed commits
• includes documentation
• adds unit tests

Release note:

NONE

[nojnhuh]

/milestone v1.15

[codecov]

Codecov Report

Attention: Patch coverage is 80.85106% with 9 lines in your changes are missing coverage. Please review.

Project coverage is 62.81%. Comparing base (400ea01) to head (5503a41).
Report is 8 commits behind head on main.

Files	Patch %	Lines
exp/controllers/resource_reconciler.go	80.85%	5 Missing and 4 partials ⚠️

Additional details and impacted files

@@            Coverage Diff             @@
##             main    #4810      +/-   ##
==========================================
+ Coverage   62.77%   62.81%   +0.03%     
==========================================
  Files         199      199              
  Lines       16569    16588      +19     
==========================================
+ Hits        10402    10420      +18     
  Misses       5389     5389              
- Partials      778      779       +1     

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[jackfrancis]

/lgtm
/approve

[k8s-ci-robot]

LGTM label has been added.

Git tree hash: 350ea60d241caca354b6f347b498dbd9ce04fce3

[k8s-ci-robot]

[APPROVALNOTIFIER] This PR is APPROVED

This pull-request has been approved by: jackfrancis

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