Bug 33196: Generalize pseudonymization system preference description

Bug 33196: Generalize pseudonymization system preference description

The Pseudonymization system preference description in
the staff interface is: "Disable/Enable pseudonymization
to comply with GDPR for personal information. Patrons and
transactions will be copied to a separate table for
statistics purpose."

GDPR is a European Union (and, at time of writing, UK) law;
it makes the system preference look irrelevant for
libraries outside this area. However, this is not correct:
pseudonymization may be useful for libraries anywhere.

This generalized the system preference description and
only uses GDPR as an example instead of the only purpose.

It also updates the fields listed to more closely reflect
the labels on the patron form.

To test:
* Search for "Pseudonymization" in the systme preferences
* Verify that the description of the system preference is
  very GDPR
* Apply patch
* Verify the system preference description is improved

https://bugs.koha-community.org/show_bug.cgi?id=33196
Signed-off-by: David Nind <david@davidnind.com>
Signed-off-by: Lucas Gass <lucas@bywatersolutions.com>
Signed-off-by: Tomas Cohen Arazi <tomascohen@theke.io>