Only install essential tools during initial qt installation

Qt's online installer by default installs Qt Design Studio, Qt Creator, CMake, Ninja and some version of latest Qt stable Qt (this is likely a recent change).

When running the online installer for the first time (not the maintenance tool) make sure to only install Creator, ninja and CMake.

And only then install the explicitly specified package (or default Qt package).

Make sure to output the executed command, for easier copy-pasting.