Various Plugins: Simplify return FilePath statements

Change-Id: Ia9efb86f722caca1492b577d51442f1f23b804b4
Reviewed-by: <github-actions-qt-creator@cristianadam.eu>
Reviewed-by: Qt CI Bot <qt_ci_bot@qt-project.org>
Reviewed-by: Orgad Shaneh <orgads@gmail.com>

src/plugins/qtsupport/qtversionmanager.cpp

@@ -397,7 +397,7 @@ static FilePaths gatherQmakePathsFromQtChooser()
 {
     const QString qtchooser = QStandardPaths::findExecutable(QStringLiteral("qtchooser"));
     if (qtchooser.isEmpty())
-        return FilePaths();
+        return {};
 
     const QList<QByteArray> versions = runQtChooser(qtchooser, QStringList("-l"));
     QSet<FilePath> foundQMakes;