fix: typos, uniform ctype in userinfo, jwt ES stored in TextField

[rglauco]

fixed typo in provider settings
uniformed content-type userinfo response for SPID and CIE
changed fetched_entity_statement jwt to TextField
chore: stick to django v4

[sallner]

Sorry for the late questions @peppelinux, but why are you sticking to Django 5 at the moment? Is there a specific reason for that? If you do not support Django 5 it is possible to use the trove classifier for 4 only, but this limits the installation of my application. I used it with django 5 currently and it did not seem to break. Do I miss something?

[peppelinux]

=4.0,<5.0

means that you can use all the version equal or major of 4 and inferior than 5

[sallner]

Thanks for that information. I know what it means, but not what the reason was for this restriction. Let's discuss it further down in #298 .