Bug 28604: Prevent double encoding of MARC::Record::MiJ->to_mij output

Bug 28604: Prevent double encoding of MARC::Record::MiJ->to_mij output

This patch fixes a double-encoding issue with MiJ output.

Mojolicious' *text* renderer encodes the passed information according to
the request context. [1]

MARC::Record::MiJ->to_mij, conveniently encodes the string before
output [2].

This causes double encoding.

So the solution to this situation, is to use the *data* renderer, which
doesn't perform any encoding [3].

To test:
1. Apply the regression tests patch
2. Run:
   $ kshell
  k$ prove t/db_dependent/api/v1/biblios.t
=> FAIL: Tests contain diacritics and fail!
3. Have a record with diacritics
4. Try the API routes for fetching a biblio:
   $ curl --location --request GET 'http://localhost:8080/api/v1/public/biblios/144' \
          --header 'Accept: application/marc-in-json'
   (replace the record id with the one you've chosen)
=> FAIL: Boo, double encoding
5. Bonus point: you can try it on the non-public route, but you need
   more configuration boilerplate (basic auth, permissions). If you look
   at the fix, you will understand the tests cover it and no need to
   complicate yourself.
6. Apply this patch
7. Repeat 2
=> SUCCESS: Tests pass!
8. Repeat 4 (and maybe 5)
=> SUCCESS: No double encoding! Yay!
9. Sign off :-D

[1] https://metacpan.org/release/MRAMBERG/Convos-0.5/view/local/lib/perl5/Mojolicious/Guides/Rendering.pod#Rendering-text
[2] https://metacpan.org/dist/MARC-File-MiJ/source/lib/MARC/Record/MiJ.pm#L111
[3] https://metacpan.org/release/MRAMBERG/Convos-0.5/view/local/lib/perl5/Mojolicious/Guides/Rendering.pod#Rendering-data

Signed-off-by: Tomas Cohen Arazi <tomascohen@theke.io>
Signed-off-by: Lucas Gass <lucas@bywatersolutions.com>
Signed-off-by: Martin Renvoize <martin.renvoize@ptfs-europe.com>
Signed-off-by: Jonathan Druart <jonathan.druart@bugs.koha-community.org>