Bump github.com/elastic/go-licenser from 0.4.2-0.20230608174114-6eca7dbbc006 to 0.4.2 in /internal/generator

Bump github.com/elastic/go-licenser from 0.4.2-0.20230608174114-6eca7dbbc006 to 0.4.2 in /internal/generator #45