Update setup-building.rst

Author: KilJaeeun

getting-started/setup-building.rst

@@ -240,7 +240,7 @@ still build properly).
 Optimization
 '''''
 
-To get an optimized build of Python, ``configure --enable-optimizations``. 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.
+To get an optimized build of Python, ``configure --enable-optimizations``. 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::
 
    $ ./configure --enable-optimizations --with-lto