[ES] Adapt the "es-campos-semanticos" script

[BoboTiG]

Fixes #2140

We are still missing lowercase entries. But, it seems they are just duplicates of current entries, right? If so, we could adapt the template to check for the current entry and the entry lowercased.

[BoboTiG]

It's a good thing that we catch the change. For instance, in our tests, we have:

{{moluscos|y|alimentos}}

And trying that in any Spanish wikipage will result in a big red error:

Error de Lua en Módulo:error en la línea 19: PLANTILLA OBSOLETA.

So our tests need to be updated.

The new way is to use the "csem" template: {{csem|moluscos|alimentos}} (note that adding y will result in the same big red error).