fix: include namespace creation in release manifest

[thisthat]

Fixes #852

Example of run that the ns file is correctly created: https://github.com/thisthat/lifecycle-controller/actions/runs/4183048159/jobs/7246906287

[sonarcloud]

Kudos, SonarCloud Quality Gate passed!   

0 Bugs
0 Vulnerabilities
0 Security Hotspots
0 Code Smells

No Coverage information
No Duplication information

[codecov]

Codecov Report

Merging #855 (454f688) into main (0edd9c1) will decrease coverage by 0.50%.
The diff coverage is n/a.

Additional details and impacted files

@@            Coverage Diff             @@
##             main     #855      +/-   ##
==========================================
- Coverage   58.52%   58.03%   -0.50%     
==========================================
  Files          97       89       -8     
  Lines        7552     7072     -480     
==========================================
- Hits         4420     4104     -316     
+ Misses       2939     2820     -119     
+ Partials      193      148      -45     

Impacted Files	Coverage Δ
...anager/controllers/keptnwebhookcontroller/certs.go
klt-cert-manager/kubeutils/query.go
klt-cert-manager/kubeutils/secret.go
klt-cert-manager/eventfilter/eventfilter.go
klt-cert-manager/kubeutils/certificates.go
...okcontroller/keptnwebhookcertificate_controller.go
...rs/keptnwebhookcontroller/webhook_configuration.go
...llers/keptnwebhookcontroller/certificate_secret.go
...lers/lifecycle/keptnworkloadinstance/controller.go	82.51% <0.00%> (+0.89%)	⬆️
...ptnworkloadinstance/reconcile_prepostdeployment.go	90.90% <0.00%> (+9.09%)	⬆️
... and 1 more

Flag	Coverage Δ
component-tests	41.79% <ø> (+0.27%)	⬆️
klt-cert-manager	?

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

[thschue]

lgtm