tools.licenseservice update should stop the existing qtlicd process

As a user I want to be able to update the License Service installation using the Qt Online Installer without unexpected behavior.

The user may have the License Service running while using the Qt Online Installer to update the same service executable to newer version.

The tools.licenseservice installscript.qs should stop the qtlicd(.exe) process before doing the update.

This may have a side-effect that applications consuming an existing reservation may be stopped due to the License Service being shut down. The applications should shut down gracefully and allow the user to save changes before quitting.