Automate adding build webhooks to Gitea

[j-zimnowoda]

Is your feature request related to a problem? Please describe. It it cumbersome to add web hooks to gitea.

Describe the solution you'd like A clear and concise description of what you want to happen. By creating a build from source code stored in Gittea app, webhooks should be added automatically by gitea-operator

Describe alternatives you've considered n/a

Additional context Add any other context or screenshots about the feature request here.