FIX: [STUDIO-2235] FlushFileBuffers on conf bak

Change-Id: I26ddf05c8b7105bb9226930e64a736cdc9be4e4f

src/libslic3r/utils.cpp

@@ -897,6 +897,8 @@ CopyFileResult copy_file(const std::string &from, const std::string &to, std::st
         goto __finished;
     }
 
+	FlushFileBuffers(handledst);
+
 __finished:
     if (src_wstr)
         delete[] src_wstr;