Remove spurious export and @publish of non-existing fill_cpp_data_raw

[dnuy]

The current version breaks during precompile stage as it has a spurious export and @publish of a non-existing method fill_cpp_data_raw. Just removing the two respective lines fixes this.

This was what I grabbed out of a CI build using GridapEmbedded:

ERROR: LoadError: UndefVarError: `fill_cpp_data_raw` not defined
Stacktrace:
 [1] top-level scope
   @ ~/.julia/packages/GridapEmbedded/r8izR/src/Exports.jl:4
...

[ericneiva]

Hi, @dnuy, thanks for the fix :)