cmake: require just 2 boost component by default program_options, regex

Tested locally that build succeeds with all other components being
header-only or unused by now.

`regex` is only needed for Boost <1.76, see
https://www.boost.org/releases/1.76.0/

cmake/IfcOpenShellConfig.cmake.in

@@ -30,11 +30,8 @@ if(NOT "${IFCOPENSHELL_BOOST_USE_MULTITHREADED}" STREQUAL "")
     set(Boost_USE_MULTITHREADED ${IFCOPENSHELL_BOOST_USE_MULTITHREADED})
 endif()
 set(Boost_COMPONENTS
-    system
     program_options
     regex
-    thread
-    date_time
     iostreams
 )
 find_dependency(Boost CONFIG COMPONENTS ${Boost_COMPONENTS})