Merge topic 'refactor-ostream-usage'

c225897ca0 cmExportCMakeConfigGenerator: Optimize `std::ostream::operator<<` calls
bdece1c754 Refactor: Optimize `ostream::operator<<()` calls for some generators

Acked-by: Kitware Robot <kwrobot@kitware.com>
Acked-by: buildbot <buildbot@kitware.com>
Merge-request: !10079