Remove broken technical assistance text in footer

Originally there was a link pointing to the FAQ page but it was removed
in commit e14b7b67fb because by default the FAQ page in CONSUL only
contains a placeholder text.

We aren't sure where this link should point:

* FAQ page, only if the FAQ page is published
* Help page, only when the help feature is enabled
* CONSUL technical documentation page

So, for now, we're choosing the easiest solution which is removing the
text completely.

config/locales/es/general.yml

@@ -213,7 +213,6 @@ es:
       conditions: Condiciones de uso
       consul: aplicación CONSUL
       consul_url: https://github.com/consul/consul
-      contact_us: Para asistencia técnica entra en
       copyright: CONSUL, %{year}
       description: Este portal usa la %{consul} que es %{open_source}.
       open_source: software de código abierto