fix: remove incorrect compile flags

to reproduce spurious abort insert:

src/silo/preprocessing/preprocessor.cpp:61
Database Preprocessor::preprocess() {
   tbb::parallel_for(tbb::blocked_range(0, 1), [](const auto i){
      throw std::runtime_error("");
   });
   ...
}

CMakeLists.txt

@@ -9,7 +9,7 @@ message(STATUS "Build type: ${CMAKE_BUILD_TYPE}")
 
 set(CMAKE_CXX_FLAGS "-Wall")
 set(CMAKE_CXX_FLAGS_DEBUG "-g -fsanitize=address")
-set(CMAKE_CXX_FLAGS_RELEASE "-O3 -static-libstdc++ -static-libgcc")
+set(CMAKE_CXX_FLAGS_RELEASE "-O3")
 
 # Work-around only for MacOS
 if (${CMAKE_SYSTEM_NAME} MATCHES "Darwin")