Update setup-building.rst

Author: KilJaeeun

getting-started/setup-building.rst

@@ -238,7 +238,7 @@ still build properly).
 
 
 Optimization
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 To get an optimized build of Python, ``configure --enable-optimizations --with-lto``. This sets the default make targets up to enable Profile Guided Optimization (PGO) and may be used to auto-enable Link Time Optimization (LTO) on some platforms. Note that configuration including this option takes time to configure. If you want to learn more about these options, please  see `Configure > Performance options <https://docs.python.org/3/using/configure.html?highlight=lto#performance-options>`_ ::