Fix a possible race condition affecting parallel builds configured with
``--enable-experimental-jit``, in which :exc:`FileNotFoundError` could be caused by
another process already moving ``jit_stencils.h.new`` to ``jit_stencils.h``.
Fix a possible race condition affecting parallel builds configured with
``--enable-experimental-jit``, in which :exc:`FileNotFoundError` could be caused by
another process already moving ``jit_stencils.h.new`` to ``jit_stencils.h``.