Move app logo to main executable

Moves more branding information out of the plugins.

Change-Id: I71575f268dd8f2860f4da56101b0e3d9442df367
Reviewed-by: <github-actions-qt-creator@cristianadam.eu>
Reviewed-by: Alessandro Portale <alessandro.portale@qt.io>

src/plugins/plugins.qbs

@@ -26,7 +26,6 @@ Project {
         "conan/conan.qbs",
         "copilot/copilot.qbs",
         "coreplugin/coreplugin.qbs",
-        "coreplugin/images/logo/logo.qbs",
         "cpaster/cpaster.qbs",
         "cpaster/frontend/frontend.qbs",
         "cppcheck/cppcheck.qbs",