Check how we can make it clearer that we replace watcher image tag from config with kustomization

[c-pius]

Description

Follow-up from https://github.com/kyma-project/lifecycle-manager/pull/1929/files#r1787653199

It may be unclear that we always overwrite the image set in skr-webhook/resources.yaml with a kustomization value from config/watcher/kustomization.yaml. We should try to make this explicit by either

• removing the iamge field entirely from skr-webhook/resources.yaml (if possible)
• adding a comment that it will be overwritten from X
• setting it to a dummy value so that it is clear that we will overwrite it and it doesn't have meaning

Reason

More explicit. We may try to change the value here and are then surprised why the change doesn't take effect

AC

• image that is used for skr-webhook is explicitly known.