Removal of "Next" Button Interaction on Installer Welcome Page

User Story:

As a new potential customer trying to evaluate any of Qt products, I want to get as quickly as possible to actually trying out the product in order to evaluate the value. 

AC:

• once the user has authenticated her/himself in the Qt Maintenance tool, he sees the "Welcome to the Qt Installation!" message and the loading of the metadata starts immediately (see attached image)
• the user does not need to press the "Next" button to start the metadata loading