Merge topic 'various-refactorings'

8352a2d12f cmFileCommand.cxx: Optimize `cmStrCat()` calls
e2c9bb7f54 cmFindBase.cxx: Optimize `cmStrCat()` calls
16a1fa9e35 cmFindBase.cxx: Check `DebugMode` and exit early to reduce indentation
6751b3d9b4 cmLocalGenerator.cxx: Optimize `std::ostream::operator<<()` calls
11bf70f968 FindPackageHandleStandardArgs: Remove the unneeded symbol from the message

Acked-by: Kitware Robot <kwrobot@kitware.com>
Tested-by: buildbot <buildbot@kitware.com>
Merge-request: !10013