Add ca: "pagination" entry

[ddnexus]

[benkoshy]

@AbelToy

Thank you again for your contribution to the ca locale.

We are in the process to improve the labelling of pagy helpers in order to comply with the ARIA standards.

We are seeking your advice with the pluralized translation of the "Page", "Pages" label, for each required plural listed below:

    page_label: 
      one: "?"
      other: "?"

Please, feel free to post a comment with your translations. You don't need to create a PR (if you don't want to): we can manage it crediting you.

Thank you in advance for your help!