Update CMakeLists.txt to Sylvian suggestion

Author: mcbarton

CMakeLists.txt

@@ -447,17 +447,10 @@ if(EMSCRIPTEN)
     xeus_wasm_compile_options(xcpp)
     xeus_wasm_link_options(xcpp "web,worker")
     if (SYSROOT_PATH MATCHES "@")
-      execute_process(
-          COMMAND ln -s ${SYSROOT_PATH}
-      )
-      set(SYSROOT_PATH_ORIGINAL ${SYSROOT_PATH})
-      set(SYSROOT_PATH "./sysroot/")
+       string(REPLACE "@" "@@" SYSROOT_PATH "${SYSROOT_PATH}")
     endif()
     if (XEUS_CPP_RESOURCE_DIR MATCHES "@")
-      execute_process(
-          COMMAND ln -s ${XEUS_CPP_RESOURCE_DIR}
-      )
-      set(XEUS_CPP_RESOURCE_DIR "./${CPPINTEROP_LLVM_VERSION_MAJOR}")
+       string(REPLACE "@" "@@" XEUS_CPP_RESOURCE_DIR "${XEUS_CPP_RESOURCE_DIR}")
     endif()
     target_link_options(xcpp
         PUBLIC "SHELL: -s USE_SDL=2"
@@ -473,11 +466,6 @@ endif()
 
 if(XEUS_CPP_BUILD_TESTS)
     add_subdirectory(test)
-    if (SYSROOT_PATH_ORIGINAL MATCHES "@")
-      execute_process(
-          COMMAND ln -s ${SYSROOT_PATH_ORIGINAL} "${CMAKE_CURRENT_BINARY_DIR}/test/"
-      )
-    endif()
 endif()
 
 # Installation