fix(shipyard-controller): Proceed with service deletion if the service is not present on the configuration service anymore

[bacherfl]

Closes #7446

This PR adds a check for a ErrServiceNotFound error when trying to delete a service from the configuration service. If the shipyard controller detects such an error when attempting to delete a service from a project, it will proceed with deleting the service from the database as well, to keep the state of the project consistent with what is available in the project's git repo

How to test:

1. Create. project
2. Create a service within that project
3. Delete the service directory from the upstream (or the configuration-service, if no upstream is configured)
4. Try to delete the service via the Bridge
5. The service should now be deleted successfully
   (6. Try to recreate the service with the same name - this should also work)

[sonarcloud]

Kudos, SonarCloud Quality Gate passed!   

0 Bugs
0 Vulnerabilities
0 Security Hotspots
0 Code Smells

No Coverage information
0.0% Duplication

[codecov]

Codecov Report

Merging #7459 (d080028) into 0.13.x (4a92524) will increase coverage by 0.02%.
The diff coverage is 87.50%.

@@            Coverage Diff             @@
##           0.13.x    #7459      +/-   ##
==========================================
+ Coverage   57.78%   57.81%   +0.02%     
==========================================
  Files         508      508              
  Lines       29408    29429      +21     
  Branches     1381     1381              
==========================================
+ Hits        16994    17013      +19     
- Misses      11203    11204       +1     
- Partials     1211     1212       +1     

Impacted Files	Coverage Δ
shipyard-controller/common/configurationstore.go	87.83% <78.57%> (-0.69%)	⬇️
shipyard-controller/handler/servicemanager.go	74.78% <100.00%> (+1.88%)	⬆️

Flag	Coverage Δ
shipyard-controller	57.55% <87.50%> (+0.11%)	⬆️

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